From the passage identify the spin-off games release in the universe of Clash of Clans. Display the results in a comma separated format.

Context: Clash of Clans is a 2012 free-to-play mobile strategy video game developed and published by Finnish game developer Supercell. The game was released for iOS platforms on August 2, 2012, and on Google Play for Android on October 7, 2013.

The game is set in a fantasy-themed persistent world where the player is a chief of a village. Clash of Clans tasks players to build their own village using the resources gained from attacking other player's villages with troops; earning rewards, buying them with medals or by producing them at their own village. The main resources are gold, elixir and dark elixir. Players can conjoin to create clans, groups of up to fifty people, who can then participate in Clan Wars together, donate and receive troops, and chat with each other. The minimum number of players of a Clan War is thirty. 

Clash of Clans was released to generally positive reviews from critics.

Four spin-off games in the same universe of Clash of Clans were developed by Supercell. The first, Clash Royale, was released in 2016. The other three, Clash Quest, Clash Mini, and Clash Heroes, were announced in April 2021. Clash Quest development was discontinued on 17 August 2022.[9

Answer: Clash Royale, Clash Quest, Clash Mini, Clash Heroes