You shoot with the Tab key, sorry about this awkward key, i realized just now with comments that i made the build without remapping the keyboard controls ^^'
If you have a controller, the controls are a bit less awkward, you jump with A and shoot with X (Xbox button layout)
Oh well that's what i get for playtesting mainly with a controller :/ I'll edit the page and tell the proper controls and all
Sorry again , huge noob mistake on my part, hope this doesn't affect the experience too much