Gameplay in Kingdom Hearts III is similar to its predecessors, with hack and slash combat,[8] which director Tetsuya Nomura stated would be along the lines of the system seen in Kingdom Hearts II, with an evolution similar to what was seen from Kingdom Hearts to Kingdom Hearts II, and closely tied to the gameplay in Kingdom Hearts 3D: Dream Drop Distance.[9][10][11] He also revealed that the handheld games of the series were where he could experiment with the combat mechanics, and that some of the well-received additions could appear in Kingdom Hearts III.[9][10] Nomura noted that new gameplay elements are the "skeleton" of the game, saying development starts with a "fun element" for gameplay or system to then build the story and concept around.[12] Additionally, the development team "always want to try something new", taking previously introduced mechanics and making small "tweak[s]" to them so they are customized for Kingdom Hearts III.[13]
Sora returns as the main playable character, once again joined in the party by Donald Duck and Goofy,[14] with the ability to have two additional characters join the party for a total of five-player parties. This is an increase from previous main entries in the series, where players were limited to two additional party members at any given time along with Sora.[15] Certain parts of the game have Riku and Aqua as playable characters.[16] Describing the gameplay, Nomura called the action "pretty frantic", as well as "really flashy and exciting. The enemy AI is a lot more intricate, too, and I think the gameplay will reflect that new dynamic balance."[17] Sora can perform magic, with a new, powerful tier of each spell available to him, similar to what Aqua has available to her in Kingdom Hearts 0.2: Birth by Sleep – A Fragmentary Passage.[18] Magic performs differently in underwater sections of the game, with Kingdom Hearts III introducing a new spell, Water.[19] Team-up attacks are also featured, which combine Sora and various party members into one attack.[20][21] Players can equip various abilities for Sora and his party members, with the system to do so "an evolution of sorts" from the system used in Kingdom Hearts II.[22] Character summons make a return from previous entries, this time known as "Links", where an additional character joins the battle to assist the player with specialized attacks.[23]