I've recently uploaded a reference sheet I've been using to BGG:
https://boardgamegeek.com/filepage/2926 ... nce-2-x-a5
It's quite compact (the game takes a lot of table space already) and includes the shorthand for all the options available to the players on their turn along with attacking rules/modifiers and key terms such as Knockback, Igniter etc.
It actually went through several iterations as I was adding/removing/rewording stuff for optimal usability and it was super helpful both when learning the game and introducing new players. That being said, if you have any feedback let me know.