Second Form

Second Form is a Formchange in Kingdom Hearts III. It grants Sora clothing based on his outfit from Kingdom Hearts II and gives him access to familiar abilities. It is triggered by the Kingdom Key, Starlight, Midnight Blue, Phantom Green, and Dawn Till Dusk. Although each of these Keyblades has a nominally different formchange determined by the Keyblade—"Second Form", "Second Form S", "Second Form M", "Second Form P", and "Second Form D", respectively—only Second Form S actually differs from the others.

Appearance
Second Form changes Sora's clothes into the same colors and style of the clothes he wore in Kingdom Hearts II. While wearing his original outfit during the Olympus episode, Sora's clothes do not change. In addition, when using the max-level Shotlock, Sora's clothes will also briefly change to his Kingdom Hearts II style, even when not in Second Form.

Mechanics
Second Form grants Sora several of his abilities from Kingdom Hearts and Kingdom Hearts II that are otherwise unusable outside of the Formchange. At any time, Sora can use a situation command finisher that will also terminate the formchange. Each time he fills the Situation Gauge, this finisher is replaced with a more powerful finisher—first Stun Impact, then Sonic Blade, and finally Ars Arcanum. Second Form S replaces Ars Arcanum with Ancient Light.