The Shy Bandit

The Shy Bandit is a mini-boss that appears in Paper Mario: Color Splash. He is a Black Shy Guy who apparently was banished from his homeland. He wears a red mask resembling glasses on the usual Shy Guy mask. When he appears, he will throw a marker on the area he intends to suck up all the color from and begin running toward that spot. Usually, he is a sizable distance from that area. Mario must then race toward the marker. If Mario picks up the marker before the Shy Bandit gets there, he disappears and Mario gets 300 coins. If Mario doesn't get there in time, he will bump into the Shy Bandit instead, initiating a battle; at this point, the Shy Bandit will attack first by blinding Mario with paint or summoning enemies, such as Hammer Bros and Buzzy Beetles to attack. If Mario defeats the Shy Bandit, he receives 300 coins and a chance to get his card. If Mario fails to get to the Shy Bandit before he sucks up the paint from a level, the 'colorless spots cleared' marker on the level reverts to the default 0% (with a few exceptions). The Shy Bandit can attack even areas colored back to 100%.

It is possible that the Shy Bandit is a member of the Koopa Troop, as he can summon minions of Bowser to assist him in battle. This has not yet been confirmed nor denied however.

Trivia

 * Despite being a mini-boss, enemies summoned with enemy cards do not run away in front of the Shy Bandit. They attack him as normal instead.
 * The Shy Bandit's mask closely resembles the mask worn by Ms. Mowz, another character from the Paper Mario series.