The current "nerf" on First Strike is not elegant.
I think it might be better to remove the 24 hp limit from the ability and instead give Negate First Strike to most high end units that are meant to be immune to heroes oneshotting them.
Which brings a few questions we need to answer, in particular :
-Did we have any reason for not using the solution in the first place? I don't remember any but it was a long time ago.
-Which units do we want to negate first strike?
-What about heroes?
For the units, I think normal units, common and uncommon creatures are fine to be killed by a first striking unit in one hit. Most of these don't have 25 hp per figure to be relevant anyway.
Rares and Very Rares we should look at individually.
We have Angel, Phoenix, Arch Angel, Gorgons, Stone Giant, Behemoth, Great Wyrm, Colossus, Great Drake, Hydra, Doom Bat, Efreet, Chaos Spawn, Storm Giant, Sky Drake, Djinn, Vampire, Wraiths, Death Knights and Demon Lords.
Arch Angel already has Negate First strike so it's not relevant.
Angel isn't really meant to be a powerful combat unit so I think it doesn't need protection.
Phoenix I'm unsure of but probably doesn't need protection either, as Life is weak against hero strategies either way and counters them by an unstoppable quantity of unit, not by a strong doomstack (unless it's a doomstack of archangels or its own heroes).
Gorgons and Stone Giants are strong enough for a rare creature to not need this special treatment either, I think if a hero can first strike these, that's fine, and just means the owner should upgrade to very rares faster. Storm Giants, same deal, with their ranged armor piercing shots they are difficult enough as is, at least for a rare.
Behemoth definitely needs the protection as it's slow and meant to be a "tank" unit.
Wyrms probably don't need it since they can move first and kill the heroes if they are the defender, although flying heroes might be able to counter them. However a unit that digs itself into the ground definitely is something I'd expect to be immune to first strike attacks based on common sense, so probably better to add the ability to them.
Colossus have powerful ranged attacks and can hit invisible heroes, I don't see the need for an extra layer of protection.
Great Drakes and Sky Drakes need it most, being just too slow to avoid being taken out by the heroes on turn two and having no ranged attacks whatsoever.
Hydras are a joke for any decent engame hero anyway so it's fine to leave them as is.
Chaos Spawn's gaze comes before first strike either way.
Djinn are a pain to deal with, let's not make it even worse.
Doom Bats on the other hand, if the retaliation damage was unavoidable would be a lot more dangerous, hitting at least twice for 8 damage each, instead of only once on their first turn before they die. I think adding it makes sense for such a fast creature anyway.
Efreet, not sure, and honestly their melee damage isn't good enough to be relevant against stronger heroes so probably no need.
Vampires and Wraiths also do little to be able to pierce through an endgame hero's armor so they are fine as is, although I would expect a Vampire to be able to negate first strike attacks due to having abnormally fast reflexes.
Death Knights and Demon Lords probably need it.
So as a summary :
I think we should add NFS to Behemoth, Great Drake, Sky Drake, Death Knight, Demon Lord and maybe to Great Wyrm, Vampire, Doom Bat.
As for heroes, the AI is bad at positioning these strategically and will likely get hit by a first strike attack so at least the better melee heroes and those with high fortress garrison priority should probably gain the ability. Although they often have enough armor that they can survive hits from enemy heroes anyway so I'm not entirely sure.
I think it might be better to remove the 24 hp limit from the ability and instead give Negate First Strike to most high end units that are meant to be immune to heroes oneshotting them.
Which brings a few questions we need to answer, in particular :
-Did we have any reason for not using the solution in the first place? I don't remember any but it was a long time ago.
-Which units do we want to negate first strike?
-What about heroes?
For the units, I think normal units, common and uncommon creatures are fine to be killed by a first striking unit in one hit. Most of these don't have 25 hp per figure to be relevant anyway.
Rares and Very Rares we should look at individually.
We have Angel, Phoenix, Arch Angel, Gorgons, Stone Giant, Behemoth, Great Wyrm, Colossus, Great Drake, Hydra, Doom Bat, Efreet, Chaos Spawn, Storm Giant, Sky Drake, Djinn, Vampire, Wraiths, Death Knights and Demon Lords.
Arch Angel already has Negate First strike so it's not relevant.
Angel isn't really meant to be a powerful combat unit so I think it doesn't need protection.
Phoenix I'm unsure of but probably doesn't need protection either, as Life is weak against hero strategies either way and counters them by an unstoppable quantity of unit, not by a strong doomstack (unless it's a doomstack of archangels or its own heroes).
Gorgons and Stone Giants are strong enough for a rare creature to not need this special treatment either, I think if a hero can first strike these, that's fine, and just means the owner should upgrade to very rares faster. Storm Giants, same deal, with their ranged armor piercing shots they are difficult enough as is, at least for a rare.
Behemoth definitely needs the protection as it's slow and meant to be a "tank" unit.
Wyrms probably don't need it since they can move first and kill the heroes if they are the defender, although flying heroes might be able to counter them. However a unit that digs itself into the ground definitely is something I'd expect to be immune to first strike attacks based on common sense, so probably better to add the ability to them.
Colossus have powerful ranged attacks and can hit invisible heroes, I don't see the need for an extra layer of protection.
Great Drakes and Sky Drakes need it most, being just too slow to avoid being taken out by the heroes on turn two and having no ranged attacks whatsoever.
Hydras are a joke for any decent engame hero anyway so it's fine to leave them as is.
Chaos Spawn's gaze comes before first strike either way.
Djinn are a pain to deal with, let's not make it even worse.
Doom Bats on the other hand, if the retaliation damage was unavoidable would be a lot more dangerous, hitting at least twice for 8 damage each, instead of only once on their first turn before they die. I think adding it makes sense for such a fast creature anyway.
Efreet, not sure, and honestly their melee damage isn't good enough to be relevant against stronger heroes so probably no need.
Vampires and Wraiths also do little to be able to pierce through an endgame hero's armor so they are fine as is, although I would expect a Vampire to be able to negate first strike attacks due to having abnormally fast reflexes.
Death Knights and Demon Lords probably need it.
So as a summary :
I think we should add NFS to Behemoth, Great Drake, Sky Drake, Death Knight, Demon Lord and maybe to Great Wyrm, Vampire, Doom Bat.
As for heroes, the AI is bad at positioning these strategically and will likely get hit by a first strike attack so at least the better melee heroes and those with high fortress garrison priority should probably gain the ability. Although they often have enough armor that they can survive hits from enemy heroes anyway so I'm not entirely sure.