Ah ha, I think I've got it!
I'll be adding a fix for this in the next update. If you guys could go and try him out after our next update and let me know if there are any more problems with him that'd be great.
It seems to be, as Alteration mentioned, that if you kill the minions too quickly it was confusing the code that removes the shield. I did some experiments with Taunt as Narciss suggested, but it didn't seem to have any detrimental effect. If that is still an issue after the update I'll have another look at it.
- Eloom likes this