Hi,
Here’s my laser defender version. Made some modifications to the game.
Short description:
- free motion within the game space
- the enemy ships are pushed around by the player projectiles
- power up drops using probability when an enemy is killed
- power ups: health, invincibility (for 7 seconds) and rapid fire
- a new enemy spawns as soon as another is killed (not just when all of them are killed)
- each enemy chooses its firing rate on spawn
- added controller support as well, which seems to be working on web build (just hit Tab to switch between keyboard controls and controller. you can still use the keyboard when controller is toggled, but the motion seems off. honestly i recommend using a controller, feels more fluid and engaging)
https://www.gamebucket.io/game/825eaae5-8c6e-4bd6-9852-6d8366be6b77
For extra fun, when invincible, ram the other ships for pretty fireworks 
Just don’t do it when you’re not invincible and listen to the shield’s audio cue to know when it’s going to drop, or count to 6 and step away.
There’s no time limit on the rapid fire, but if you get hit, you lose it.
I also didn’t put a cap on the health you can amount to, so you can keep adding up health points if you don’t get hit, but since health drops give you less health than what getting hit takes away and you don’t know exactly how much health you have, it seems to ballance it out
Hope you enjoy it and let me know your thoughts 