The mouse is the enemy the game. It has powers like telekinessis, manipluating fire, the power to make illusions, to grow and shrink objects, and can apparently shoot cheese beams out of it's eyes. It is first seen in the intro cutscene kidnapping your owner to steal all the treats. At the end of the game, Scratch Cat trys to stop the mouse, the mouse shrinks him then. Scratch then calms him down and asks him why he is doing the evil stuff. The mouse tells him that he's stealing the treats. Scratch asks him, "Why didn't you just ask?" The mouse replys back to him, "I never thought about that." Then the mouse frees the owner. Resulting in the pacifist ending. Which is a reference to Undertale. The other ending is the genocide ending. Also a reference to Undertale. To get the ending you have to find key, then you click on the key to activate a cutscene, Scratch unlocks a door and trys to literally kill the mouse. The mouse summons minions. Soon Scratch defeats them all and defeats the mouse.