Kirby: Planet Robobot is a 2.5D side-scrolling platform game that uses traditional Kirby platform gameplay; the aim of the game is to guide Kirby towards the end of the level while utilizing his copy abilities to defeat enemies and interact with the environment. This time around, Kirby is defending Popstar from the corrupt Haltmann Works Company, which aims to mechanize the planet and steal its natural resources. The new gameplay mechanic introduced in this title is Robobot Armor, a mech suit with copy abilities similar to Kirby's own. The Robobot Armor is much more powerful than Kirby and can interact with obstacles that he may not be able to pass on his own, but its large size sometimes means Kirby will need to exit the suit and proceed on foot. In addition to the mech gameplay, Kirby has access to three copy abilities that are new to the series: Doctor, Poison, and ESP. All copy abilities can be accessed at will by scanning in compatible amiibos, including alternate costumes that can only be obtained through figures made specifically for this game.
Alternate modes include Team Kirby Clash, an action RPG that supports up to 4 players; Kirby 3D Rumble, in which Kirby moves around an arena to defeat enemies as fast as possible while aiming for a high score; Meta Knightmare Returns, a speed-oriented mode in which the player controls Meta Knight through modified versions of the levels from story mode; and the Arena and True Arena modes that return from other platformers in the series.