How to win with a “weak” Knight?

And what if it’s not there? Later, I might already have the highest-level army in my castle, but the guild isn’t available. And it seems like Antimagic level 3 is available, but they might not grant Wisdom. Today, I encountered a really annoying warlock; I was playing as a Beaver, but the point is the same. He gathered about 40 gargoyles, 20 griffins, 60 centaurs, 40 thieves, and 35 sprites, and he’s charging ahead with a spell power of 8. In general, I struggled with him; he easily captured any castle. Luckily, I found an artifact that gives +12 to defense and gave it to my strongest hero, and I managed to defeat him. Of course, there was no Wisdom; the only wise hero, a wizard, was 0-1-4-2, which is only good for casting two Lightning spells and running away.