There are a lot more combat moves now
"Movesets are a lot larger this time. There are a lot more combat moves, much more than just the couple of punches and a kick," says Cerny noting that the limited combat options in the original were a major source of complaints from players. "The moveset just keeps expanding the more you play, so by the end of the game there will be a huge number of combat moves that Knack can do. You unlock them with an in-game currency and there's a skill-tree with 30-odd moves and variants to unlock. This was really in response to feedback that we got on the first game – people said they wanted much more variety."
There are elaborate punches and kicks, grapples, flip-kicks, and a shield now. "Do you remember Fist of the Northstar?" Cerny asks. "If you hold down the punch button you do a Fist of the Northstar style multi-punch now." This is just one of the more satisfying combat options, along with new super moves triggered by crystals in the levels that make Knack briefly invincible and extend his reach for a few seconds.
Playing co-op also changes the nature of the combat. "When we watched people playing co-op we'd see them punching each other a lot and messing with each other," Cerny laughs. "It happened so much that we decided that we'd try and make that part of the game." Rather than just slapping each other around now, players are able to weaponize each other. Standing behind your partner and executing moves turns the other player's Relics into projectiles.