Good job making the game !
The gameplay is a bit confusing because it lacks feedback when bullets hit people. You don't really know if what you are doing has an impact until the enemy dies. It would have been also good to have some feedback about Oswald health and level progress. Overall try to focus on adding some feedbacks so the player can understand what's going on. And finally, the game is hard and the cheat button helps. I know it's really hard to balance a game but I think for a game jam it's better to have an easy game than a hard one. So next time I think you should tweak the values to make it easy by default without needing a cheat.
Congrats !