I play a mardu mobilize deck with Ragavan. Whenever his ability activates after dealing combat damage, my game crashes, and I can't reopen the game till, I beleive, I time out and lose the match, I don't know since when I try and reopen the game it crashes right as its rejoining the match. I'd reported a bug earlier this week, but this confirms that it was Ragavan's ability causing the bug. This happened after the most recent update, please patch it.