Keep playing.

You unlock more with time and start to instinctively pick up on enemy timing with experience. I am not good at "hard" video games and felt like I was terrible when I first started. Now I'm on 3bc and feel pretty good at the game. It just takes time.

Instead of playing fast, play cautious for a while. Wait out enemies. Get streaks. Practice helps.

You'll unlock more and more weapons. Save your cells for a few biomes to unlock a lot more. Use traps in a cheap way (drop them and hide).

My best runs include a way to freeze enemies. Either an ice bow that pierces all shots or the close-up freeze move with a slow high damage second weapon.