- "A nother day, a nother test."
- ―Shamus ready to test
KM-4YT, also known as Shamus, is a test-bot at the Hero Factory, who tests weapons.
KM-4YT is a test bot for testing new weapons to see if they are safe or not. Not many people care about Shamus, they only care about the weapons. Shamus does his own testing sometimes. It makes its own cores to test on himself because it gets boring sometimes. KM-4YT's friends sometimes call it a hero.
Shamus is very complex. When it is doing a test for a weapon it gets a bit scared. If Shamus is doing one of his own testing corses he gets competitive unless it is with someone he knows, then it would be both funny and serious.