While playing with a friend in online co-op, after finishing the hall dungeon, the game had crashed for me and sent me to the main menu. Then when I was invited to join the lobby again my game locked up and froze, closed the game, relaunched, and upon joining the lobby again I had 0 items and artifacts in my inventory, 300-something emeralds, and 25 enchant points. I was nearly level 30, had a power level of 35, and 3 unique items in each top spot, and minimum power 26 artifacts filling all three slots.