I enjoy LitRPG (not virtual game ones tho, hard to care about the 'stakes'), but I do feel its a bit ridiculous to have actual creatures behave MMO style. Taunting/CC abilities are fine, but the creatures should act like sapients would once the skill wears off. Or explain that they gain resistance too it, or something for why he can't maintain it 100% also. Or explain that the gargoyles/dungeon creatures are basically golems that only operate they way they were told too at creation or something, to explain the 'game script' exploitability. Not just go into a 'real world' dungeon and have things react like video game bots.