I'm working on some homebrew spellcasters, and I want them to have Conjure Animals on their spell list. The question I have is, how do I balance an encounter with this in mind? The spellcaster is only CR 2 by itself, but it can conjure 8 CR 1/4 beasts which immediately turns a Medium encounter for 4 2nd level characters into a Deadly encounter for 4 4th level characters. I understand the party would sensibly focus the caster, but if the caster maintains distance and concentration then it's an easy TPK. How should I handle this? Is it a bad idea to put this spell on a monster? It really fits the spellcaster in question, so I really want to grant it.