Horizon of Darkness

By the way, at the sixth level of enchantment, it should permanently change the creature, but with limited slots. Or was it supposed to be a separate skill?

I understood that you only want combat enchantment. The sixth level works until the end of the battle, and then it's over.
If you need an enchantment that lasts until the end of the game for a minion, I'll add it. It will simply allow you to enchant a maximum of 1 minion per in-game day.