The genre gets the gacha name from ‘ gachapon’, a type of vending machine popularised in Japan that dispenses capsule toys in a randomised manner. In an Uppsala Universitet thesis, ‘ What Aspects of Gacha Games Keep the Players Engaged’, authors Rentia and Karaseva describe gacha as ‘a monetisation model that emerged in video games, containing randomised virtual in-game rewards with varying rarities.’ Gachapon vending machines at Yodobashi-Hakata in Fukuoka, Japan.

In essence, the mechanic encourages players to spend in-game currency for a chance to get a high-rarity item or character. A gacha game is a specific type of video game whereby ‘gacha’ represents a core game mechanic.