So I totally fell in love with the Kirby card. (alternate art variant of P.P.P.P)

Are there any decks build around it's auto-win? Any cards that synergize particularly well? Still rather new to getting back into the game so I would really appreciate any help.

Unfortunately that card is extremely gimmicky, fairly weak as a creature and not worth the effort overall as there are things that will allow you win quicker with less setup, while the set up is very similar.

It needs tons of set up which is something that Light as a civilization outside of the shield zone has trouble with, you need blue for draw in order to get your PPPPs and run Emergency Typhoon (of which thanks to twinpacts you can run 8 of) to get 1 PPPP in the grave, then bank 1 in mana and then you'll likely have to search for the other two, if 1 of them is in shields that really sucks because you additional have to scry for it and Emeral it out but the biggest issue is the one in your hand which is very likely to be discarded and the win effect triggering at the start of the turn, not right away so it can be interrupted by your opponent's actions. The creature has no form of protection and has meager power for a cost 5 so it is very easy to remove via spell or snipe with a Mach Fighter and alike.

There is other gimmicky cards like this which do this better, primarily Dueland, Ultimate Galaxy Universe, Shakogairu and the End of Universe with Shako and EoU being the most competitive as they can be looped into and instantly trigger without any interrupting chance of the opponent.

There is more Kirby artwork cards in the game, DMRP-18 has a few.