Neutral

The winning position in this game plan is dtilt distance.

You don't have to always dtilt from here, but moving into this position with dtilt is obviously necessary too sometimes.

You can use different jump drifts/ or dash's or dash -> wd, dash in wd down any or all of those are great for setting this position up from true neutral. All of these movement options have strengths and weaknesses, you have to learn how your opponent will try and beat you trying to get to this range.

Then from there you can safely threaten kirby and if he tries to roll into you from this position you can just jump back freely into a dair/ aerial.

If kirby gets impatient and tries to move in with an aerial you can jump back and throw out an aerial to protect yourself too.

You can punish roll in different ways. But yeah, this is basically it. It's like a vortex. When you get a hit get to this position again as quickly as you can.

Grabbing the roll behind and uthrowing can lead into huge punishes, though you have to be better at juggling.