In my third game so far, Vetrar was wondering around my territory. I was on my way to engage him, already having killed Aegethon.

But then something strange happened - Vetrar got near an undamaged shard I owned, and he decided to attack. He moved to its square, I got the 'shard under attack' message, and the shard took well over 50% damage. But Vetrar, like all other monsters that attack shards, was gone.

Where did he go? I think he was just 'deleted.'

Later on in the game, I tried to break down the SK's door, but I only had 1 of 2 keys. I cast eyes of the eagle all over the map, but no sign of Vetrar.

It seems Vetrar should NOT be capable of attacking a shard, since that removes him from the game, and makes it impossible to win.