quite nice concept, would like to see a more fleshed out version
There already is one. It's called Dicey Dungeons. This is honestly a bit of a rip off of it.
They just both use dice to defeat opponents. There's a lot of dice-related deck building games out there and there's bound to be some things that have the same format. Another game like that is Die in the Dungeon, which is also similar to these two
