Nice to see a roguelike cardbuilder here!
This idea is easily expandable in a full-fledged game, it reminds me of Onitama, a board game where you have units and “movement cards”. It was a particular 5x5 Chess.
I think even this game can easily and definitely be better just by reducing a lot the board. Wandering one tile at a time isn’t the best, but if the board is 4x4 or 5x5 then your idea can fit without any problem (like Michael Brough’s games, check them out).
For the rest, I liked this one and with some general polish in terms of design and fun you can go far. Congratulations for this impressive entry!