So I needed to get become better acquainted with the uxntal opcodes AND I wanted to fiddle around with Decker. So I made a uxntal opcode flashcards deck.
https://jache.re/assets/opcodes.html
I added it to the literate-uxn repository, under "practice".
https://codeberg.org/thgie/literate-uxn
Decker is awesome!