complete gacha; kompu gacha
A monetization mechanic in mobile/social games where a rare item is awarded only after the player collects a full set of other items, typically through random paid draws. Often associated with controversial spending incentives.
See also: ガチャ
Complete gacha is a mechanic that once became a problem in social games.
In that game's complete gacha, you couldn't get the rare character unless you collected all the types.