It is a interesting little rat game attacking outsiders and don't eat poison. If I may ask is this game both your first game? It has nice potentials for sure I think.
It has a good base to work more on it. Like you could polish the UI, make indeed more levels and use more powerups (what are the powerups?) fix the movement and combat cause if I wanted to go up or down I went diagonally this was cause before I pressed 2 keys. And add some knockback on the enemies.
Overall interesting game that could be a good game when worked out more!