Also the end of game screen has things that don't make sense, like "the swarm is now void touched". Not sure if that is something I should be trying to do, and if so how.
To make the game more challenging, it might be useful to only allow so many weapons to be unlocked at once, and have different bosses require different strategies to defeat. E.g. have slow required because sometimes enemies come in really fast, or have a set of waves that require stun locking just a few strong enemies.