Receiving nothing on death and being unable to redo levels definitely makes grinding impossible. I like the game's concept though.
Viewing post in Spikklubba (incremental update) comments
Thanks for testing the game out. I started with letting you keep 50% of the resource when you die, but then you could just replay the same level and die on purpose to farm, and it felt boring. I'm absolutely not sure what is best in this scenario, but I opted for a hard punishment so you needed to Survive in order to both get all the resources and proceed in the dungeon progression.
If the goal is being a difficult game that's fine, but given the enemies get stronger pretty quick, I feel the goal could be to encourage progressing instead of discouraging remaining. Like (just an example) tying branches past a threshold in the upgrade tree to a level beaten, or currencies for later upgrades only dropped by stronger enemies, so that there's motive to move forward but still your failed attempts aren't for nothing if you need a little strength to push through a level. Otherwise a lot of the floors kinda boil down to either getting good... or just waiting for rng to give a favorable layout. That being said, it's a very fun format, and some of the later enemies definitely keep you needing to focus quick.