I was playing Top 50, I had around 18 cards and 20 HP left, my opponent had 100 HP and 6 cards left, when the game suddenly counted it as my loss.
He was using a Quanta drain strategy, and I killed his only two damaging creatures using Owl's Eye across two turns. After I killed the last one, he replaced it with yet another upgraded Devourer, causing him to have every single creature slot filled with Devourers.
After it showed yet another large amount of -1s to represent the Quanta drain, it suddenly switched to the "You have lost!" screen even though I probably would have won had the game continued. He had no weapon, nor used anything that could cause 20 damage. I checked the rules, but there didn't seem to be any automatic win condition for having a full party of Devourers. He didn't even have any permanents other than pillars...
Edit: Ah, thank you. Dead before I know what hit me...
