>Must be written in any dialect of Lisp. This includes, but is not limited to Common Lisp, Scheme, Emacs Lisp, and Clojure.

from https://itch.io/jam/autumn-lisp-game-jam-2018

From the last 2-3 Jams, IMHO, you can see a tendency towards exo-lisps as many entries were done with Fennel or some in Urn.