As it was raised that economy spells are overpriced/too weak, I'm going to review them and will adjust them for the next update as necessary, so do tell your opinion here.
I will exclude Heavenly Light and Nature's Eye from the list as those have a different primary function and resource production is just an extra benefit.
I also exclude Evil Presence as the military disabling effect is the primary one, removing unrest reduction is secondary.
Likewise I will explode Philosopher's Stone as it's also a military purpose building (combat spell skill).
First question is, how many turns as "return of investment" do we find acceptable?
Economy spells have to compete with military or other spells whose return of investment is impossible to calculate. So we don't really know what counts as "good" here. I'd say anything over 50 turns is probably too slow as in that much time, a significant part of your empire can be conquered by an enemy who researched a military purpose spell that can turn the tide against you, but this is just a random guess.
Next, how do we measure the value of casting skill used?
If we measure the spells in the time span of 50 turns, each 1 point of casting skill we have can cast 50 MP worth of spells.
At the common tier, it costs an approximate of 40 SP to gain a casting skill, so each point of MP used is worth 0.8 SP+1 MP, a total of 1.8 power invested.
At uncommon, we can assume ~100 SP for casting skill, so 3 power for 1 casting cost.
At rare, 200 SP for a casting skill, a total of 5 power spent per casting cost.
At very rare, 400 SP for a casting skill, 9 total power spent per casting cost.
(These values assumed we research the spell around the beginning of the spell tier, so 20, 50, 100, 200 total casting skill in the tiers)
1. Change Terrain
960 RP, 32 MP, 0 UP
Being uncommon, the total power investment is 32*3 = 96 per cast and 960 for research.
Benefit is roughly 1 more maximal population per cast, which equals 2 base production and ~2 base gold. There are of course bonuses, so the effective amount gained is more like 3 per turn of each, but production is worth twice as much as gold (purchasing cost multiplier) so it's effectively +9 gold a turn, which, without alchemy is equivalent to 4.5 power.
Assuming you cast the spell 6 times on each of 8 cities, that's 48 uses, so each use has 960/48 = 20 RP research cost.
So each use costs 116 power and gives back 4.5 per turn for a return of investment value of 25 turns. With Alchemy, this is twice as effective (12 turns).
So overall ROI is around 25 turns with reasonable usage.
This assumed we targeted a Swamp tile. Desert is mostly the same (lose production but gain 0.5 more pop), Hills and Forests are slightly worse but only marginally (lose 3% production) Mountains much worse (lose 3.5% production, and only 0.75 pop gained on each of the two castings).
I think that's fair overall, no change needed.
Except, this assumed the new population appears immediately, while in reality you have to wait for it.
The immediate effect is +5 growth and being able to convert 1 farmer to worker every 4 uses, if and only if you were overfarming, to provide 6 gold worth of hammers.
2. Abundance
3600 RP, 150 MP, 2 UP
This is roughly equivalent to 6 good uses of Change Terrain (Swamp to Grasslands). Neither the research nor the casting cost is 6 times larger so this has better ROI than Change Terrain. Casting cost is 33% more valuable at rare, but the research cost is less than 4 times higher and the MP cost less than 5 times higher instead of 6 times making it fairly even.
2 upkeep is divided between 12 uses of "+0.5 population" so the +2.25 above is only reduced by 0.166 which is a marginal difference.
Overall this spell is mostly equal in effectiveness and ROI to change terrain. Which honestly, isn't that great for a higher tier spell, but this one ALSO works on terrain where Change Terrain is unusable - you can boost population coming from shores, rivers, grasslands, etc, while Change Terrain can only boost Forest, Desert, Swamp and Hills effectively and Mountain semi-effectively. There is a downside though, which is hitting the population caps so this spell can only reach peak effectiveness on cities at around 12-14 max pop as base terrain. Higher than that will, with a Granary, exceed 25, while lower would yield less than +6 max pop.
That's an absurdly narrow range for the spell being better than an uncommon, so this spell probably needs to be buffed. A higher boost to population would just make it even easier to hit the population cap so a lower cost seems the better solution. Probably 120 MP with 1 upkeep would be fair?
For both of these spells, the primary problem is that the effect is not immediate. We could somewhat improve that by changing how population growth is calculated, by increasing the effect of max population on growth. However, doing so would, in general, speed up city growth early on and slow it down past midway, as well as increasing the value of high max pop spots drastically and making Nomads much worse as a race unless their racial growth compensates for the lack of Granary.
However, these spells are supposed to provide a slower, more long term benefit, in exchange for having a much greater potential (basically you can turn even max pop 3 spots into pop 25 metropolises). So maybe removing the max pop cap of 25 could be a better direction to take instead of a cost reduction or buffing the immediate spell effect. This has already been mentioned in another thread and other than the difficulty of implementation, I don't think an argument against the feature was raised. The only one I can think of is the increase of luck factor over terrain available but it's not significant - terrain better than 25 max is rare. This would however be a drastic buff to Guardian and Nature Omniscient.
-------------------
Unrest.
As several spells offer unrest reduction, it's best to calculate that in advance.
1 unrest removal is equivalent to 1 population, so just like Change Terrain, it's worth the equivalent of 9 gold, 4.5 power per turn.
-------------------
3. Gaia's Blessing
2400 RP, 100 MP, 3 UP
This has 3 effects.
a. 2 unrest reduction. This is worth 4.5 power/turn each.
b. More production from Forest tiles. Assuming an average of 4 tiles, this is 24% more production.
c. Converting Deserts (and Volcanoes). This is effectively a free use of Change Terrain for each of those tiles.
Assuming you can cast this on 20 cities, the RP cost adds 120 to the total investment, which at rare is 500 power for a total cost of 620 power.
Change Terrain had a converted cost of 116 so each Desert is worth that much value. Assuming 1 desert per city (in reality it'll be 10 around two cities and none on the others unless playing Dry land), this is effectively an (almost, it's actually 10% per turn so in 10 turns but that's less than our targeted ROI time) immediate refund of 116, reducing your cost to 404.
24% more production, with a pop 18 city that has 8 farmers and 10 workers, plus Sawmill and Smithy for 30 hammers base production is worth +7.2 hammers, equal to +7.2 power.
Unrest reduction is worth 9 total so we have 16.2 power produced per turn, but 3 spent on upkeep, so the total gain per turn is 13.2.
504/13.28 is 37.95 so the return of investment is reasonably average.
If we only cast it on cities with 2-3 or more Desert tiles, it can be drastically better than this.
I think we don't need to buff it, or at most, buff the specialized parts of the effect, like one or more of these changes, to bring out more specialized potential :
-Volcano converted to Forest instead of Hills
-Forest Production raised to 12% or 15% instead of 9%.
-Natural resources (ores, wild game etc) cannot be destroyed in the area by Raise Volcano
-Faster removal of Volcanoes, Corruption and Deserts (tho Corruption removal is already faster than the other two.)
4. Stream of Life
1280 RP, 120 MP, 4 UP
Three effects again.
a. -3 Unrest is worth a total of 13.5 power per turn.
b. Doubled growth
c. Heal units to max each turn
You generally either have low population and benefit greatly from double growth, or have high population and can use the unrest reduction. So I'll treat these as mutually exclusive, equivalent effects, and will only calculate based on A. (C is a military effect that's hard to quantify)
Assuming this will be cast on 8 cities, 160 RP is spent per use on research. At uncommon, the casting cost is worth 360 power.
So the total cost is 520. Benefit is 13.5 per turn minus 4 upkeep, placing the ROI at 54 turns, ignoring the military benefits.
Not that great but it's okay for an uncommon?
We did ignore the doubled growth benefit, saying it's equivalent to +3 people which isn't true - at it's peak it can be way more than that, although early on and later it's less. So the snowballing potential from this is huge.
We also ignored the fact this can and will be useful on all future small cities you build or conquer and helps repair damage (lost population) from battles as well as heals your units.
Overall I think this spell is good as is, at best minor changes might be necessary, like 1 more unrest removal or 1 less upkeep. We should also consider that Life doesn't have much strong military option such as summoning or combat damage spells to research, at best they can buff which is powerful but way less cost-effective than other realms - so the pressure for a fast return on investment isn't there. You can generally do better by only building fewer buffed armies that don't suffer any losses, and buffing the conquered cities with Stream of Life than if you buffed more stacks and ignored buffing the cities.
Also, if we remove the 25 population cap, the doubled growth can be drastically more powerful on the right terrain/wizard build.
Finally, in my experience, AIs who had this spell early always perform very well, which would indicate the spell is definitely not underpowered.
5. Altar of Peace
1280 RP, 120 MP, 4 UP
Assuming you buffed 8 cities with this, the RP cost is 160, total power cost is 520.
RP produced is 24, but at 4 upkeep it's only 20 gained per turn.
This puts ROI at 26 turns which is excellent, especially on uncommon. You only needs an average of +40 relation to get this amount which is reasonably reachable, even in high wizard count games.
No change needed.
6. Sanctify
960 RP, 70 MP, 1 UP
Total cost is, assuming at least 48 uses, 20+3*70 = 230 power.
Power generated is 3, but maintenance is removed to save 3 gold on average which is worth 1.5 power. Total benefit is 4.5 power per turn minus the upkeep so 3.5.
This makes the return of investment 65 turns.
Definitely on the slow side but this is an infinitely spammable spell, that is meant to be used for entirely peaceful gameplay when military options are not relevant. It doesn't need to compete with any other spell for that reason - it's the only thing you can cast if you already used all other city buffs.
Probably fine as is, or maybe we could reduce the MP cost to 60 which would put ROI at 57 turns, or to 50 which would be a ROI of 48 turns. It's also worth noting that Alchemy does increase ROI somewhat by doubling the value of gold saved.
Considering Raise Volcano also costs 50 and generates 3 power, 50 might be reasonable. Divine Order is no longer uncommon to allow spamming this spell early on at a reduced cost, although that still is something you can do later on - but by then casting skill is worth more so it's not that much of a problem.
Raise Volcano does not remove upkeep though so it's not as good as Sanctify and Volcanoes also have a change to revert to mountains. They can however generate extra resources if you cast them on your own territory but that's generally not worth it except on tundra and maybe Desert/Swamp terrain. Maybe if Volcanoes added 3-5% production, casting it on own territory could be slightly more viable? It would make it worse as a city curse though.
7. Inspirations
4800 RP, 200 MP, 4 UP
+100% production bonus.
Assuming this is cast on 20 cities, the RP cost per use is 240, the total power cost is 1240.
Assuming 30 hammer base production again in cities, this adds 30 production which is equivalent to generating 30 power, 26 with upkeep.
This makes ROI 1240/26 = 47 turns.
Slightly better than Sanctify and Stream of Life although worse than Gaia's Blessing but doesn't depend on terrain, and production is a very useful resource that is probably most effective at snowballing and more importantly, winning the game through building more units than your enemy.
Looks ok to me but definitely not strong, maybe a minor casting cost reduction could help?
4800 RP cost is definitely on the high end of the spectrum as an initial investment though, but the only way to reduce that would be to swap with Mass Healing which might be overcosted at 4800 RP?
8.Prosperity
2400 RP, 175 MP, 2 UP
+50% Gold bonus. Assuming the same baseline city, 18 population will produce 36 base gold, the Marketplace adds 8 more for a total of 44.
The amount gained is thus 22, which is equivalent to only 11 power or production, 9 if also considering the upkeep cost.
Upfront RP cost divided by 20 cities is 120 RP. Total power cost is 995 which is almost as high as Inspirations for a much weaker effect.
ROI is 110 turns, absolutely horrible and hard to justify. Probably a drastic reduction in casting cost or boost in effect is necessary.
Overall, the spell is less than half as effective.
Gold does have the benefit of being directly convertible to mana which production does not, but even then this spell seems too weak.
9.Dark Ritual
4000 RP, 150 MP, 0 UP
Converted power cost is 950.
Power gained is 24 without a retort or spell combo.
This makes the ROI 39.6 turns which is fair, especially for a non-buffing realm.
1 Unrest would reduce this by 4.5 per turn if it was actually unremovable but more often than not, you will remove the unrest or already had more removal than needed in the first place. Including the unrest effect, ROI is still 48.71 turns which is not that great.
Maybe a casting cost of 130 could work better here?
10.Warp Node
4000 RP, 120 MP, 0 UP
Assuming an average node to be worth 20 total power, this gives you 10 power and removes 10 power from your opponent.
Cost is 800 power, benefit is 20, making ROI 40, mostly the same as Dark Rituals.
Of course, removing enemy resources is worse than gaining your own unless the player count is low, but at the very least this is the expected ROI if you are targeting the final, strongest opponent in the game. If you only use it to gain power, ROI will be 80 which is worse, but you still have the option of only warping nodes with large auras.
No change needed but if we reduce the cost of Dark Ritual we should also reduce this to 100-110.
11. Drought
3200 RP, 150 MP, 2 UP
Cost is 910 power.
It is expected to remove around 100% production bonus from the targeted city, which removes 30 hammers.
The city also loses 6 base population, which is another 12 hammers.
A total of 42 hammers, 42 power value.
ROI is 21.6 turns which is amazingly good but let's not forget this is a city curse, not a buff, which is always suboptimal except in 1v1 situations.
No change needed.
12. Pestilence
8000 RP, 250 MP, 5 UP
I won't calculate this. It effectively reduces gold and production of an entire enemy empire to near zero. (They'll have their sawmill, smithy and ~2 people, so they get 4 gold and 10 production from a city at most. This isn't enough to pay for their garrsion, let alone any armies, even with AI advantages, and isn't enough to produce more troops either.)
If you can cast and maintain this on all enemy cities, you win the game. Yes, it takes time, but honestly, it takes less time than Spell of Mastery so it's outright a better victory condition - as long as you can protect the enchantment from Disenchant Areas.
13. AEther Binding
960 RP, 400 MP, 20 UP
Around the time you cast this first, it'll produce roughly 80 SP. Removing the upkeep that's 60 power generated per turn.
Effective power cost is 2160 - you only cast it once so can't divide the RP cost between cities.
This puts return of investment at 36 turns which is fair for an uncommon spell. You do gain the dispel benefits in addition for free though making this better than average but considering this is one of the flagship spells in the Uncommon sorcery tier, that's probably acceptable.
14. Uranus' Blessing
3200 RP, 150 MP, 5 UP
22 power gained, 5 upkeep is worth +17 a turn.
The 4 casting skill, at rare tier, is equivalent to 4*200=800 power but this is limited to overland only so let's halve the value, making it 400.
The price of the spell is 910 power, subtracting the value of casting skill, 400, as it's an instant, upfront benefit, we have 510 remaining, so ROI is in 510/17 = 30 turns.
Definitely seems good enough and we might be underrating overland skill by assuming it has equal value to combat skill - it probably is more valuable. At most we can consider shaving off 1 upkeep or 10 MP cost from this one.
I didn't include the global enchantments because their ROI is extremely dependent on map size, number of your or enemy cities, so those would be an entirely different topic and so far, no one mentioned they are underpowered. Considering their casting cost is generally less than buffing 10 cities while the effect is worth more than buffing 10 cities, I suspect they are fine compared to city buffs, even including the larger RP cost.
Edit : rare spells were miscalculated slightly. Updated. Don't change the conclusions much.
I will exclude Heavenly Light and Nature's Eye from the list as those have a different primary function and resource production is just an extra benefit.
I also exclude Evil Presence as the military disabling effect is the primary one, removing unrest reduction is secondary.
Likewise I will explode Philosopher's Stone as it's also a military purpose building (combat spell skill).
First question is, how many turns as "return of investment" do we find acceptable?
Economy spells have to compete with military or other spells whose return of investment is impossible to calculate. So we don't really know what counts as "good" here. I'd say anything over 50 turns is probably too slow as in that much time, a significant part of your empire can be conquered by an enemy who researched a military purpose spell that can turn the tide against you, but this is just a random guess.
Next, how do we measure the value of casting skill used?
If we measure the spells in the time span of 50 turns, each 1 point of casting skill we have can cast 50 MP worth of spells.
At the common tier, it costs an approximate of 40 SP to gain a casting skill, so each point of MP used is worth 0.8 SP+1 MP, a total of 1.8 power invested.
At uncommon, we can assume ~100 SP for casting skill, so 3 power for 1 casting cost.
At rare, 200 SP for a casting skill, a total of 5 power spent per casting cost.
At very rare, 400 SP for a casting skill, 9 total power spent per casting cost.
(These values assumed we research the spell around the beginning of the spell tier, so 20, 50, 100, 200 total casting skill in the tiers)
1. Change Terrain
960 RP, 32 MP, 0 UP
Being uncommon, the total power investment is 32*3 = 96 per cast and 960 for research.
Benefit is roughly 1 more maximal population per cast, which equals 2 base production and ~2 base gold. There are of course bonuses, so the effective amount gained is more like 3 per turn of each, but production is worth twice as much as gold (purchasing cost multiplier) so it's effectively +9 gold a turn, which, without alchemy is equivalent to 4.5 power.
Assuming you cast the spell 6 times on each of 8 cities, that's 48 uses, so each use has 960/48 = 20 RP research cost.
So each use costs 116 power and gives back 4.5 per turn for a return of investment value of 25 turns. With Alchemy, this is twice as effective (12 turns).
So overall ROI is around 25 turns with reasonable usage.
This assumed we targeted a Swamp tile. Desert is mostly the same (lose production but gain 0.5 more pop), Hills and Forests are slightly worse but only marginally (lose 3% production) Mountains much worse (lose 3.5% production, and only 0.75 pop gained on each of the two castings).
I think that's fair overall, no change needed.
Except, this assumed the new population appears immediately, while in reality you have to wait for it.
The immediate effect is +5 growth and being able to convert 1 farmer to worker every 4 uses, if and only if you were overfarming, to provide 6 gold worth of hammers.
2. Abundance
3600 RP, 150 MP, 2 UP
This is roughly equivalent to 6 good uses of Change Terrain (Swamp to Grasslands). Neither the research nor the casting cost is 6 times larger so this has better ROI than Change Terrain. Casting cost is 33% more valuable at rare, but the research cost is less than 4 times higher and the MP cost less than 5 times higher instead of 6 times making it fairly even.
2 upkeep is divided between 12 uses of "+0.5 population" so the +2.25 above is only reduced by 0.166 which is a marginal difference.
Overall this spell is mostly equal in effectiveness and ROI to change terrain. Which honestly, isn't that great for a higher tier spell, but this one ALSO works on terrain where Change Terrain is unusable - you can boost population coming from shores, rivers, grasslands, etc, while Change Terrain can only boost Forest, Desert, Swamp and Hills effectively and Mountain semi-effectively. There is a downside though, which is hitting the population caps so this spell can only reach peak effectiveness on cities at around 12-14 max pop as base terrain. Higher than that will, with a Granary, exceed 25, while lower would yield less than +6 max pop.
That's an absurdly narrow range for the spell being better than an uncommon, so this spell probably needs to be buffed. A higher boost to population would just make it even easier to hit the population cap so a lower cost seems the better solution. Probably 120 MP with 1 upkeep would be fair?
For both of these spells, the primary problem is that the effect is not immediate. We could somewhat improve that by changing how population growth is calculated, by increasing the effect of max population on growth. However, doing so would, in general, speed up city growth early on and slow it down past midway, as well as increasing the value of high max pop spots drastically and making Nomads much worse as a race unless their racial growth compensates for the lack of Granary.
However, these spells are supposed to provide a slower, more long term benefit, in exchange for having a much greater potential (basically you can turn even max pop 3 spots into pop 25 metropolises). So maybe removing the max pop cap of 25 could be a better direction to take instead of a cost reduction or buffing the immediate spell effect. This has already been mentioned in another thread and other than the difficulty of implementation, I don't think an argument against the feature was raised. The only one I can think of is the increase of luck factor over terrain available but it's not significant - terrain better than 25 max is rare. This would however be a drastic buff to Guardian and Nature Omniscient.
-------------------
Unrest.
As several spells offer unrest reduction, it's best to calculate that in advance.
1 unrest removal is equivalent to 1 population, so just like Change Terrain, it's worth the equivalent of 9 gold, 4.5 power per turn.
-------------------
3. Gaia's Blessing
2400 RP, 100 MP, 3 UP
This has 3 effects.
a. 2 unrest reduction. This is worth 4.5 power/turn each.
b. More production from Forest tiles. Assuming an average of 4 tiles, this is 24% more production.
c. Converting Deserts (and Volcanoes). This is effectively a free use of Change Terrain for each of those tiles.
Assuming you can cast this on 20 cities, the RP cost adds 120 to the total investment, which at rare is 500 power for a total cost of 620 power.
Change Terrain had a converted cost of 116 so each Desert is worth that much value. Assuming 1 desert per city (in reality it'll be 10 around two cities and none on the others unless playing Dry land), this is effectively an (almost, it's actually 10% per turn so in 10 turns but that's less than our targeted ROI time) immediate refund of 116, reducing your cost to 404.
24% more production, with a pop 18 city that has 8 farmers and 10 workers, plus Sawmill and Smithy for 30 hammers base production is worth +7.2 hammers, equal to +7.2 power.
Unrest reduction is worth 9 total so we have 16.2 power produced per turn, but 3 spent on upkeep, so the total gain per turn is 13.2.
504/13.28 is 37.95 so the return of investment is reasonably average.
If we only cast it on cities with 2-3 or more Desert tiles, it can be drastically better than this.
I think we don't need to buff it, or at most, buff the specialized parts of the effect, like one or more of these changes, to bring out more specialized potential :
-Volcano converted to Forest instead of Hills
-Forest Production raised to 12% or 15% instead of 9%.
-Natural resources (ores, wild game etc) cannot be destroyed in the area by Raise Volcano
-Faster removal of Volcanoes, Corruption and Deserts (tho Corruption removal is already faster than the other two.)
4. Stream of Life
1280 RP, 120 MP, 4 UP
Three effects again.
a. -3 Unrest is worth a total of 13.5 power per turn.
b. Doubled growth
c. Heal units to max each turn
You generally either have low population and benefit greatly from double growth, or have high population and can use the unrest reduction. So I'll treat these as mutually exclusive, equivalent effects, and will only calculate based on A. (C is a military effect that's hard to quantify)
Assuming this will be cast on 8 cities, 160 RP is spent per use on research. At uncommon, the casting cost is worth 360 power.
So the total cost is 520. Benefit is 13.5 per turn minus 4 upkeep, placing the ROI at 54 turns, ignoring the military benefits.
Not that great but it's okay for an uncommon?
We did ignore the doubled growth benefit, saying it's equivalent to +3 people which isn't true - at it's peak it can be way more than that, although early on and later it's less. So the snowballing potential from this is huge.
We also ignored the fact this can and will be useful on all future small cities you build or conquer and helps repair damage (lost population) from battles as well as heals your units.
Overall I think this spell is good as is, at best minor changes might be necessary, like 1 more unrest removal or 1 less upkeep. We should also consider that Life doesn't have much strong military option such as summoning or combat damage spells to research, at best they can buff which is powerful but way less cost-effective than other realms - so the pressure for a fast return on investment isn't there. You can generally do better by only building fewer buffed armies that don't suffer any losses, and buffing the conquered cities with Stream of Life than if you buffed more stacks and ignored buffing the cities.
Also, if we remove the 25 population cap, the doubled growth can be drastically more powerful on the right terrain/wizard build.
Finally, in my experience, AIs who had this spell early always perform very well, which would indicate the spell is definitely not underpowered.
5. Altar of Peace
1280 RP, 120 MP, 4 UP
Assuming you buffed 8 cities with this, the RP cost is 160, total power cost is 520.
RP produced is 24, but at 4 upkeep it's only 20 gained per turn.
This puts ROI at 26 turns which is excellent, especially on uncommon. You only needs an average of +40 relation to get this amount which is reasonably reachable, even in high wizard count games.
No change needed.
6. Sanctify
960 RP, 70 MP, 1 UP
Total cost is, assuming at least 48 uses, 20+3*70 = 230 power.
Power generated is 3, but maintenance is removed to save 3 gold on average which is worth 1.5 power. Total benefit is 4.5 power per turn minus the upkeep so 3.5.
This makes the return of investment 65 turns.
Definitely on the slow side but this is an infinitely spammable spell, that is meant to be used for entirely peaceful gameplay when military options are not relevant. It doesn't need to compete with any other spell for that reason - it's the only thing you can cast if you already used all other city buffs.
Probably fine as is, or maybe we could reduce the MP cost to 60 which would put ROI at 57 turns, or to 50 which would be a ROI of 48 turns. It's also worth noting that Alchemy does increase ROI somewhat by doubling the value of gold saved.
Considering Raise Volcano also costs 50 and generates 3 power, 50 might be reasonable. Divine Order is no longer uncommon to allow spamming this spell early on at a reduced cost, although that still is something you can do later on - but by then casting skill is worth more so it's not that much of a problem.
Raise Volcano does not remove upkeep though so it's not as good as Sanctify and Volcanoes also have a change to revert to mountains. They can however generate extra resources if you cast them on your own territory but that's generally not worth it except on tundra and maybe Desert/Swamp terrain. Maybe if Volcanoes added 3-5% production, casting it on own territory could be slightly more viable? It would make it worse as a city curse though.
7. Inspirations
4800 RP, 200 MP, 4 UP
+100% production bonus.
Assuming this is cast on 20 cities, the RP cost per use is 240, the total power cost is 1240.
Assuming 30 hammer base production again in cities, this adds 30 production which is equivalent to generating 30 power, 26 with upkeep.
This makes ROI 1240/26 = 47 turns.
Slightly better than Sanctify and Stream of Life although worse than Gaia's Blessing but doesn't depend on terrain, and production is a very useful resource that is probably most effective at snowballing and more importantly, winning the game through building more units than your enemy.
Looks ok to me but definitely not strong, maybe a minor casting cost reduction could help?
4800 RP cost is definitely on the high end of the spectrum as an initial investment though, but the only way to reduce that would be to swap with Mass Healing which might be overcosted at 4800 RP?
8.Prosperity
2400 RP, 175 MP, 2 UP
+50% Gold bonus. Assuming the same baseline city, 18 population will produce 36 base gold, the Marketplace adds 8 more for a total of 44.
The amount gained is thus 22, which is equivalent to only 11 power or production, 9 if also considering the upkeep cost.
Upfront RP cost divided by 20 cities is 120 RP. Total power cost is 995 which is almost as high as Inspirations for a much weaker effect.
ROI is 110 turns, absolutely horrible and hard to justify. Probably a drastic reduction in casting cost or boost in effect is necessary.
Overall, the spell is less than half as effective.
Gold does have the benefit of being directly convertible to mana which production does not, but even then this spell seems too weak.
9.Dark Ritual
4000 RP, 150 MP, 0 UP
Converted power cost is 950.
Power gained is 24 without a retort or spell combo.
This makes the ROI 39.6 turns which is fair, especially for a non-buffing realm.
1 Unrest would reduce this by 4.5 per turn if it was actually unremovable but more often than not, you will remove the unrest or already had more removal than needed in the first place. Including the unrest effect, ROI is still 48.71 turns which is not that great.
Maybe a casting cost of 130 could work better here?
10.Warp Node
4000 RP, 120 MP, 0 UP
Assuming an average node to be worth 20 total power, this gives you 10 power and removes 10 power from your opponent.
Cost is 800 power, benefit is 20, making ROI 40, mostly the same as Dark Rituals.
Of course, removing enemy resources is worse than gaining your own unless the player count is low, but at the very least this is the expected ROI if you are targeting the final, strongest opponent in the game. If you only use it to gain power, ROI will be 80 which is worse, but you still have the option of only warping nodes with large auras.
No change needed but if we reduce the cost of Dark Ritual we should also reduce this to 100-110.
11. Drought
3200 RP, 150 MP, 2 UP
Cost is 910 power.
It is expected to remove around 100% production bonus from the targeted city, which removes 30 hammers.
The city also loses 6 base population, which is another 12 hammers.
A total of 42 hammers, 42 power value.
ROI is 21.6 turns which is amazingly good but let's not forget this is a city curse, not a buff, which is always suboptimal except in 1v1 situations.
No change needed.
12. Pestilence
8000 RP, 250 MP, 5 UP
I won't calculate this. It effectively reduces gold and production of an entire enemy empire to near zero. (They'll have their sawmill, smithy and ~2 people, so they get 4 gold and 10 production from a city at most. This isn't enough to pay for their garrsion, let alone any armies, even with AI advantages, and isn't enough to produce more troops either.)
If you can cast and maintain this on all enemy cities, you win the game. Yes, it takes time, but honestly, it takes less time than Spell of Mastery so it's outright a better victory condition - as long as you can protect the enchantment from Disenchant Areas.
13. AEther Binding
960 RP, 400 MP, 20 UP
Around the time you cast this first, it'll produce roughly 80 SP. Removing the upkeep that's 60 power generated per turn.
Effective power cost is 2160 - you only cast it once so can't divide the RP cost between cities.
This puts return of investment at 36 turns which is fair for an uncommon spell. You do gain the dispel benefits in addition for free though making this better than average but considering this is one of the flagship spells in the Uncommon sorcery tier, that's probably acceptable.
14. Uranus' Blessing
3200 RP, 150 MP, 5 UP
22 power gained, 5 upkeep is worth +17 a turn.
The 4 casting skill, at rare tier, is equivalent to 4*200=800 power but this is limited to overland only so let's halve the value, making it 400.
The price of the spell is 910 power, subtracting the value of casting skill, 400, as it's an instant, upfront benefit, we have 510 remaining, so ROI is in 510/17 = 30 turns.
Definitely seems good enough and we might be underrating overland skill by assuming it has equal value to combat skill - it probably is more valuable. At most we can consider shaving off 1 upkeep or 10 MP cost from this one.
I didn't include the global enchantments because their ROI is extremely dependent on map size, number of your or enemy cities, so those would be an entirely different topic and so far, no one mentioned they are underpowered. Considering their casting cost is generally less than buffing 10 cities while the effect is worth more than buffing 10 cities, I suspect they are fine compared to city buffs, even including the larger RP cost.
Edit : rare spells were miscalculated slightly. Updated. Don't change the conclusions much.
