Drop System

The Drop System is a feature used in Kingdom Hearts 3D: Dream Drop Distance. It allows the player to switch control between Sora and Riku, allowing each to progress independently through the game. One character is presumed to be "asleep" while the other is active. The player will drop into the next character once the Drop Gauge is depleted, or they can drop manually by touching the "Drop" button that appears on the World Map, in the main menu, or in the pause menu.

Development
Following an interview with Tai Yasue, the Drop System was developed to increase the thrill of the game and to keep Sora and Riku's stories united, in contrast to Birth by Sleep, where the player has to finish a story before going on to the next one.

Story
Sora goes with Neku to the Third District, where they encounter a mysterious youth. While Neku goes to confront him, Sora is suddenly overcome with drowsiness, and he succumbs to sleep. He later wakes up to find the district empty.

After Riku fends off Beat's Spirit and the other attacking Dream Eaters in the Second District, he becomes overwhelmingly sleepy and loses consciousness. When he wakes up, he finds Joshua and Beat have gone.

Xigbar and Young Xehanort corner Sora in the World That Never Was and send him into a dream. After Xehanort shows Sora visions of his meeting Ansem, Seeker of Darkness, Sora and Ansem entering the Secret Place before the Destiny Islands fell into darkness, and Sora's visits to the different incarnations of Traverse Town, Sora suddenly passes out while chasing an illusion of Pluto.

If Riku tries to approach the Castle That Never Was before Sora defeats Xemnas, he drops off to sleep.

Mechanics
The Drop Gauge has three differently-colored bars that continuously deplete, one by one. The gauge's speed is indicated by the multiplier that accompanies it. Once the third bars empties, Bonus Time begins, and the speed multiplier is replaced with a 30 second countdown. After 30 seconds, the character will fall asleep, and player control will pass to the other character. When the player returns to the first character, play will resume where it left off. If the character drops during a boss battle, the battle will start over from scratch when they resume.

Negative Status Effects like increase the gauge's speed. The player can restore the gauge and reset the drop rate by using items like Drop-Me-Not, Drop-Me-Never, or Megalixir, and the Drop Decelerator bonus slows the gauge down, as does guarding with Wake-up Block.

Drop Bonuses
After a character drops, the "Relay Bonus" screen is shown, and the player can purchase different boosts for Drop Points, or DP. The boosts will affect the other character's gameplay. They include reduced Drop Gauge speed, temporary stat boosts, new commands or items.

DP is earned during gameplay by collecting Droplets drop by defeated Nightmares, collecting lucky items, which are detailed on the Forecast screen, or by completing Link Portals. During Bonus Time, Droplets appear more often.