Here's a big block of text, but this is the ruling. 800.4a. When a player leaves the game, all objects (see rule 109) owned by that player leave the game, any effects which give that player control of any objects or players end, and all spells and abilities controlled by that player on the stack cease to exist. Then, if there are any objects still controlled by that player, those objects are exiled. This is not a state-based action. It happens as soon as the player leaves the game. If the player who left the game had priority at the time he or she left, priority passes to the next player in turn order who’s still in the game. Example: Alex casts Control Magic, an Aura that reads, “You control enchanted creature,” on Bianca’s Wall of Wood. If Alex leaves the game, so does Control Magic, and Wall of Wood reverts to Bianca’s control. If, instead, Bianca leaves the game, so does Wall of Wood, and Control Magic is put into Alex’s graveyard. Example: Alex casts Threaten, which reads, in part, “Untap target creature and gain control of it until end of turn,” targeting Bianca’s Wall of Wood. If Alex leaves the game, Threaten’s change-of-control effect ends and Wall of Wood reverts to Bianca’s control. Example: Alex casts Bribery, which reads, “Search target opponent’s library for a creature card and put that card onto the battlefield under your control. Then that player shuffles his or her library,” targeting Bianca. Alex puts Wall of Wood onto the battlefield from Bianca’s library. If Bianca leaves the game, Wall of Wood also leaves the game. If, instead, Alex leaves the game, Wall of Wood is exiled.

Came here just to say this

​@ChunkMiwa Wouldn't Khârn fall under the "any effects that give that player control of any objects or players end" segment of 800.4a that you quoted, because of Khârn's own effect? So wouldn't he just be returned to his owner? Sorry if it's a dumb question; I'm just a 40k nerd that's getting into MTG.

@@JSgrassy not if the owner is dead

@@theaamanable Right, Andrew is Khârn's owner, and wasn't dead by the time Maximus got knocked out while controlling Khârn. So Khârn would just return to Andrew, right?

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