Rudy is a blue Gummy Bear, seen with a yellow cap, gloves and boots, and red pants. He could possibly be used to unlock a Janitor's Closet with the Spire's Secret Treasure.
Gallery
Rudy as shown in a twitch clip from the official twitch.
Rudy's walking animation. (click that [1] there!)
Rudy swinging a comically large wrench. Posted by welegi.
a screenshot of Rudy's idle frame. Posted by lostman44.
a screenshot of Rudy in Chocoa Cafe. Posted by fishibi.
Rudy's Idle during Sugar rush ripped from one of MrUnown's recent gif