Willy

Willy (as we've seen so far) is the first boss in the official steam version of Karlson. He is Billy's brother, and makes a surprise appearance after the player unknowingly walks into a huge room, and is tasked with defeating Willy. He is defeated in no particular way and can be killed with any form of damage, but you can slide under him and hit his blind spot to deal major damage. You are forced to damage Willy with the sword, and are provided with nothing else. Willy can destroy pillars.

He has many attacks

-Mini-gun

-Rocket Launcher

-Laser

-Shockwave that pushes you back to prevent it from being too easy.