Cool mechanic with the weapon swapping. The cooldown between attacks felt very long. I feel it should have either been shorter or there be some type of visual indicator of remaining time. It was also kind of small and off in the corner (at least on my 2K monitor, perhaps you didn't make it scale with screen resolution). I had to strain my eye a bit looking back and forth. The boss was cool, the different projectile patterns was cool and it was genuinely fun strafing through the projectiles.