UPDATE
After thinking of this more, the only way I can see my opponent being at 40 less than his max hp at the end is if he played a Shard of Sacrifice that I just didn't notice. Looking at the screenshot, I do believe this to be the case now. I'm only leaving this post here because his hp should not have been entirely yellow. Even if the game completely ignored the fact that he had Shard of Sacrifice up, I still only have 182 damage vs his 206 hp.
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I hit my opponent twice with a 182 power Chimera. The first hit brought him down to 64/246. The second hit brought him 'down' to 206/246. I lost the next turn due to decking. My opponent's lifebar was completely yellow when I lost even though I only had a 182 power creature vs his now 206 hp reinforcing the idea that his hitpoints went negative. I believe my opponent started the game with 174 hp and played 3 shards of divinity. I also believe the bug occurred because I did more than his starting hp in single blows.
Version: 1.293
Opponent: Arena Game vs Kapor in Platinum
Opponent cards played throughout the game: Steal, Deathstalker, Nightfall, Shard of Divinity
My deck: Instotosis with no card changes as seen here:
http://elementscommunity.org/forum/index.php/topic,32395.0.htmlEnding Opponent board:
9 Obsidian Tower (Upped)
1 Nightfall (Unupped)
3 Electrum Hourglass (Upped/Stolen)
2 Deathstalker (Upped)
3 Deathstalker (Unupped)
Quantum: 18 Darkness, 14 Death
Decksize: 40
Cards in Hand: 4
Hp: 206/246 (Entire bar is yellow even though my incoming damage is only 182)
My Ending Board:
6 Time Tower (Upped)
1 Electrum Hourglass (Upped)
1 Chimera (182/18)
Quantum: Not relevant
Decksize: 0 (lost to decking)
Cards in Hand: 1 (Shard of Readiness)
Hp: 1/100 (10 poison. 1hp is accurate. I was at 11 before the last attack. Creature damage went to Chimera)