Now this I'm putting on a bookmark. There is a ton of content here!
The attribution to the Countdown theme is obvious, imaginative, and reinforced through the gameplay. Before each battle has me so far judging and guessing and heuristicing in a way that is similar to slay the spire's "meta game". Return playthroughs I'm already getting a better grasp on the relative challenge-rating of each of the numbers, and its nice to feel that I'm being rewarded for that.
Up front, it's a little intimidating and it's hard to want to cater to myself by spending heavily, especially as the levels get harder. But I'm not sure that's a gameplay flaw. Framing them as cute blorbos definitely makes me feel better about the decision paralysis. The UI I had a little trouble with at first, between space, legibility, and understanding my interactions. Other UI stuff like the arrows for navigation were spot on though. I didn't have as much trouble with the balance/difficulty as more about how I _felt_ about judging the challenges. :)
The artstyle was very cohesively chosen. Are they all from the same pack/creator? Leaning into the strengths of the asset selection worked out a ton. Same with the levels. Felt a little bit like playing with action figures.