Thanks for playing and feedback! Yeah I completely understand. When I let others player the game (just after the jam deadline unfortunately), I noticed people sometimes being confused as to why they lost the first few times. I should probably add some audiovisual cues when you're losing and some text explaining _why_ you lost.
And yes, I usually add controller support to my multiplayer games, but for a jam game I thought keyboard would be more universally playable. (As it turns out, not everyone has multiple USB-controllers just lying around like me :p)