Drop Duchy
Imagine a card battler mixed with Tetris. (Yes, seriously.) So you play and can deploy up to eight cards which represent buildings, and each of those buildings fills a tile which then drops with a load of terrain tiles and enemy building tiles in a Tetris game. The power of your buildings and the enemies' depends on the alignment with the surroundning terrain and each other. At the end, troops from your buildings fight troops from the enemy's buildings. Each run of the game you try to go through three levels with three boss fights, and then have another go with some more abilities and cards unlocked.
So far, so good. It's actually a very interesting idea. Unfortunately, it also goes horribly wrong.
The reason is that you end up with so many potential cards to pick up (buildings, tech cards to upgrade abilities, etc.) that what cards you end up and have to play with on a run is much more luck than judgement. There's little point in game about building a deck to develop synergies when what you get is so RNG-dependent, plus the RNG of the Tetris game (you can be absolutely screwed by the order the blocks drop). Ironically, as the game develops, you have what should be more options and abilities yet it becomes harder simply by the randomness going up, and eventually you are going to feel you're playing a game where your success is more RNG than skill. And that's the point you will probably switch off very quickly.