The only one I know of is that arcane missiles requires your opponent to have a 1 health minion.
I mean, it is useful… they now have 6 less health. He’s not supposed to be trying to do a perfect thing like Zephrys did.
If it lands on a targeted spell, the target will be random though (prefers enemies).
He’s casting 6 spells for free though. Lower your expectations on how smart those should be. The fact that it’s pretty heavily weighted to use things like blizzard/flamestrike on wide boards compared to other random effects is more than good enough.