Really loved the story, gameplay is good as well, can't wait for the next update !
In my opinion, there are few features that could be improved :
- Wallet and gold : It has already been mentioned, but you can collect gold only once, even though your wallet is full (and can't buy next wallet before being full). Which means you can almost one whole level if you don't pay attention (or don't know the feature yet), and get short on gold. Maybe something could be done to avoid those issue. And in the future, if there's a need of upgrade cause the player is stuck, grinding won't be fun either.
- Boss farm : As you may need to get gold, farming on boss is the most efficient way (Second boss is done quickly, 20gold/run). But you have to go through the "cinematic" again (dialogue, sanctuary, X scene). Could it be optional, to skip everything, not just the scene, if already done once ?
- Nightmare destruction spawn : I think it was on world 2-4. I've discover the bottom pass after I've hit the core. So mobs just kept on spawning, making it almost impossible to get back to the core. Maybe would it be interesting to limit spawn if the player is more than X screen away from the core ? Or if the core wasn't hit in the last X seconds ?
Thanks again for the game, hope to conquer world 3 soon !