Your opponent can still challenge the character , and your character can still challenge, quest, use its effects, sing, etc
Then youve got the likes of Flaming Fist, which gives commander creatures you control Double Strike when they attack, or Noble Heritage, which gives commander creatures you control an ability that reads: When this creature enters the battlefield and at the beginning of your upkeep, each player may put two +1/+1 counters on a creature they control
No requests for conditioning or collectors please
"In-Game Protocol"
Game 3: My opponent played three Battle Compressor and Maxie and there was no point in ever taking a turn
So theyve had to try to find a new home plane, typically by forcing or assimilating that planes denizens