Firestorm locked up the game by killing one enemy group outright

I was on the Kobold Diamond mines level map 2 with the 3 groups of kobolds. First turn my wizard got Firestarter and Firestorm hitting most things for 4 each including the top group of kobolds. When the next turn began Firestorm again hit those top 4 kobolds for 4 damage each and killed all three of them. The game locked up as it was drawing cards for everyone and it looked like it was trying to draw cards for the dead Kobold group. This was about 2 days ago so not sure which version of Card Hunter was running then. I hope this helps!