Tip: Layer 3 backgrounds and tides disappear when you hit a message box, so plan your level around that. For example, you can add a sublevel without layer 3 at the start/midpoint, and include your message there.
This Bill-Blaster like enemy will fall down from the top of the screen endlessly and shoot at the player when they are vertically aligned. It also acts as a semi-solid platform!
It won't shoot if the player is too close, though.
If you set the Extra Bit, it will stick to the right side of the screen, which is a viable substitute for the vanilla Bullet generator in things like autoscrollers. This set of behaviors from the Sweep Blaster is a lot less polite, though, and will shoot no matter if the player is close or not.
Also note that this sprite has high chances of crashing your game in the current state of PIXI, which has a RTS instead of a RTL in its smoke-spawning routine. It's very easy to fix this by oneself but I still recommend to avoid this sprite until it's fixed (which should be super soon), in which case I'll edit this post.