Spell On the Stack Concession
When a player leaves a multiplayer lobby with a spell on the stack, the spell never resolves and the game never sees the player leave.
Such is the case here match#243717417 game#778114560 where DarknessLeo puts a spell on the stack and intentionally and Instantly Concedes. The log shows him taking these actions, but he is never removed from the game. The attached picture is taken 22 minutes later with that player's clock still running down. The game can not be completed.