The Thing in the Shoe
The bag of this ambushing crustacean contains 5 marbles: 2 red, 2 green and 1 black.
Poisonous: Anyone wounded by the thing in the shoe immediately has their life threatened (three marbles).
Ambush Predator: Anyone trying to put on a shoe in which the thing in the shoe lives is immediately attacked by it without a chance to defend themselves (the attack is performed as a challenge with five marbles instead of as a contest) as the thing tries to cut off (and eat) their foot.
Boot Shell: Shoes used as a shell by a thing in the shoes are often magical or otherwise especially precious or durable. They are worth at least one coin. As a special privilege from the coins (shoes) thus protecting it, the thing in the shoe may ignore one black marble it draws for every coin.