Robo Knack (or also refered to as Knonck) is very similar to Knack. He is known to be the retarded version of Knack as the person who is playing Knonck are likely to kill Knack by walking through lasers or hitting Knack during fights.
Here’s how to make Knack easier to enjoy via the cooperative mode:
This is a tip if you’re playing the game with (young or novice gamer) family members or friends on the couch. The solution is to play in 2-player co-op mode if you have a second PlayStation 4 controller. A second player can jump into co-op mode at any time to help out in the game as a second character named Knonck.
Tip: Knonck can help out when normal Knack’s health is low. Replenish Knack’s health by pressing on the Triangle button. Knonck can also use the area attack that Knack uses (O button + O button), consuming a small amount of sunstones in the process. The relic tornado and ranged attack are not available playing as Knonck.
Check out gameplay from Knack that shows the local two-player cooperative experience.
WARNING: Watch out if you let someone play Knonck, they may kill you in stupid ways.