Medals are a gameplay element in Kingdom Hearts Union χ. They are used to boost the player's Strength and Defense, as well as grant access to passive and active Special Attacks.
Medals are the physical manifestation of power from the future, drawn by the Book of Prophecies.
Medals are divided into six groups: Attack medals, EXP medals, Boost medals, Cost medals, Evolve medals, and Munny medals. They can be categorized by rarity based on their Special Attack Bonus.
Attack medals can be equipped to Keyblades and come in one of three types: Power (パワー, Pawā?), Speed (スピード, Supīdo?), or Magic (マジック, Majikku?). They determine the player's Strength and Defense stats, have different sets of abilities, and are preferred by certain Keyblades. A full deck consists of five Attack medals.
EXP medals provide experience for Attack medals and are used to boost their power. EXP medals are represented by Huey, Dewey, and Louie; they also are either Power, Speed, or Magic-type. Players cannot equip EXP medals; they can only be sold or fused with the Attack medals of their choice. Scrooge McDuck appears on EXP medals that lack attributes; these medals offer experience and add a Skill to the Attack medals with which they are fused.
Boost medals increase Attack medals' stats and are represented by Chip and Dale. Boost medals with the Magic Mirror on them increase Attack medals' Special Attack Bonus by 1%, while Mickey and Brooms medals either increase an Attack medal's Special Attack Bonus or allow a Roll/Re-Roll if it is at its highest value. Broom Servant medals can be fused with Fantasia Mickey medals to create Mickey and Brooms medals.
Cost medals are represented by Cid and decrease the Cost of 6-star Attack medals. They can be fused to form stacks of five or 10 that reduce an Attack medal's Cost stat by the same amount.
Evolve medals are used to evolve Attack medals. Evolve medals with the Cheshire Cat on them are used to evolve 1-star Attack medals, those with Merlin on them are used to evolve 2-star medals, those with the Fairy Godmother on them are used to evolve 3-star medals, those with Yen Sid on them are used to evolve 4-star medals, and those with Fantasia Mickey on them are used to evolve 5-star medals. Evolve medals are paired with Flora, Fauna, and Merryweather medals to evolve Attack medals with either four or five stars. Only medals of the same attribute can be fused to allow evolution.
The standard Attack medals that appear in Kingdom Hearts Union χ are called "Upright medals." They depict heroic characters and are silver or gold in coloration. "Reversed medals" depict antagonistic characters and are dark blue or purple in coloration.
List of Medals