If any character were to be "Sony's Kirby" then sackboy would fit that role. He could have his basic move set/attacks. But then also be able to use that string to attach to people, and then absorb there looks and be able to pull off a level 1 super with said character. They could have it so once he's hit by someone multiple times he goes back to normal. It's plausible, and at this point who cares what Nintendo fans have to say. It's a ps3 game. The ps3 gamers are what matter.
Sack boys got his own tools that can be implemented as attacks.the grabinator for example to throw enemys at the wall or something the creatinator to blow stuff up the grapple hook to automatically latch on to players to preform combos and his awesome signature slap,to ....slap i guess.either way theres no need to make him into a kirby when he can also use his popit as a weapon.and if he needs a special well oppening up the level creator and droppping bombs on everyone like those fun bomb survival levels on LBP would be cool.or just squish ur opponents with a rock or something.i do it in lbp all the time.either way they can have fun with sackboy and his awesome popit of death!
Sackboys popit should be his special 3. Like he'll be able to spawn bombs or pick up players or drop things on them. As long as it's not too fast then you could avoid it, so it won't be too cheap.