I was terrible at the game before I accepted how important defense was. Previously I focused hard of attack power and speed, but then you're too fragile for unexpected situations. That and much slower more considered pathing are very helpful. Look around at the rest of the level before you move or act because you might be backing yourself into a corner.

Your username is much more subtle

Edit: I decided to download the game again and do a run to see if I remembered how to play, and yeah I think my advice there is good. Carefully consider your moves before you make them, defense is very important. One thing that could help is to look up info about what to expect in a given path before going in to know if you can handle the type of stuff that you'll find in there. Eventually (if you play enough), you'll memorize them, but for example it can be very helpful to know that you'll be against a bunch of exploding enemies if you go to the "Volatile" path.