Stitch

In Kingdom Hearts II, Stitch is a summon made available by opening a chest in Hollow Bastion after the first visit to Space Paranoids. Only Stitch's Earth form is seen and his abilities comprise of his blasters and ukelele, as opposed to his true form (four arms total, antennae and hair-like spines on his back) and his powers as Experiment #626.

Role
Stitch is one of two summons during Kingdom Hearts II that makes a difference to the storyline. His first appearance is when Sora, Donald and Goofy go into the corridors leading to Ansem's study, he is seen crawling above them without their notice. During the next cutscene, he drops down onto the keyboard of the computer. Donald jumps onto the keyboard to grab him, but he jumps off. As Donald turns around, he mashes the keys, causing the MCP to be alerted.

Later, in a cutscene showing the Final Fantasy characters fighting Heartless in the The Great Maw, Stitch is seen fighting alongside them. His weapons in the cutscene are his blasters from Lilo & Stitch.

Summon
Stitch is unique as a summon because he does not actually enter the field when summoned; he instead jumps and crawls around the HUD features. His Limit attack is Ohana, in which Sora uses the Keyblade as a guitar while Stitch also plays on a ukelele. Stitch erratically replenishes HP and MP by licking the gauges.