A Knight without defense is not a Knight. Even if it's an attacking class. This means this point is very important (a clear contradiction).
Besides, Humans already have Knights. A Paladin is a specific type of Knight.
Mass buffs: Stone Skin, possibly Dodge; mass debuffs: Weakness, Curse, Slow, possibly Confusion; and then kill with Phoenix/Elementals/Chaos, etc.
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Adding to this.
The Heretic is suitable for Heroes 3, where the demon heroes were humans who betrayed their faith.
By the way, in the neighboring thread (MMH5.5), a gating system is implemented that summons a smaller number of creatures, but more quickly.
The Summoner spends 75% of their turn (instead of 50%). The summoned unit starts with 75% of its accumulated turn (instead of 0), so it starts acting after 1+0.25 = 1.25 turns from the moment of summoning (instead of 2 turns). The amount of "meat" is reduced to 15-25%.
I don't really like the numbers (the 75%), but how do you like the idea itself? Should we try to implement it in WGE? Or is the old gating system with a larger amount of "meat" but a delayed start better?