Fun take on the theme. I've seen deckbuilders that combine tetris with deckbuilding but this is the first one where the cards have adjacency bonuses. Really adds another dimension to the planning.
The adjacency effects are cool. It's a bit hard to keep track of them since the colors are written in text. You can embed the icons in the text (ex: 🟦nimble x1 ) .It's doable in unity but not sure how easy it is in godot.
I'll say that it's a bit odd that it's tetris but there's no reward for filling a row or grid. Maybe I didn't find any cards wit h that effect. But it's a situation that the player will naturally create during gameplay so it would be best to reward the player for it
My other suggestion would be that the game takes a bit long to get going. Enemy health starts off very high in the first battle. Sure, it's hard to lose but you can't do anything interesting other then maximizing grid utilization. You don't get cards with bonus effects or enemies affecting the grid until then. I think either a shorter first battle or introducing the subversions earlier will alleviate this.
The graphics are nice. I like the cute little kobolds.
The music is a bop. I had it in the background while I was writing the review and it's so good that I'm leaving it running afterwards.
Overall this is a great entry,