Just had the same happen to me (no screenshot made).
It was in the final battle with SK. Before the battle became stuck i had lost no units and almost all of my units had a (near) 100% health, and the SK was down to himself and two harbringers. Auto resolving won the battle, but half my army was destroyed, including my three heroes: Varda, Slough, and Silindros.
Auto resolving sucks.
I fought the final battle purposely without Ifris, Keplin, and Drogon because these guys had become so ridiculous overpowering during the game that i sidelined them to keep a bit of challenge in the battles against the SK and his LTs. Ifris had a combat strength of 1721, a health of 167, and a dodge of 738161; i therefor assume the presents of a nasty bug. Posting (reply #1) with screenshot when Ifris was a bit less dodgy 1.1 BIG tandus bug 17111 dodge