All of them are unlocked by default and don’t require Tubby Custards.
There are, in total, 12 colors to choose from. This option changes the color of the player’s fur in-game. However, due to limitations of the sprite style, body appearance is restricted to color only, with the ability to use custom image textures being absent. Customization differs in this game from previous entries as it allows for not only customization of body appearance, but also hat model.
Character Customization makes a return in Slendytubbies 2D.