There is no logic behind this question. I just roleplay a couple of necromancers and really like the design of Grizzles. (I mean the regular ones, not the Peerless.) Having one of those shambling behind one's character would be awesome! They're kind of cute. Edit: Also, having something that spills acid that doesn't hurt its summoner would be useful for when you have to deal with lots of lower-level mobs at once.