Every character can beat it, easily, as well.
U. Mars is not an entertaining thing to watch as one of two things will happen;
Player will treat the AI like another player: Struggle and lose to AI's sporadic reactions
Player will treat the AI like AI: Steamroll the mode with 0 problems due to the AI's blatant faults
BB's AI has improved since CT, but Score Attack and Unlimited Mars are still exceptionally simple to abuse the AI on.