The new-life immunity should be a few seconds longer, though as a tradeoff you shouldn't be able to kill enemies by running into them during this time.
Also, if I turn off the music, it should STAY OFF instead of restarting after each game.
It's a decent idea for a game, but relies too heavily on powerups - that "Star of David" one especially. I'd make the bullets a bit more powerful but less frequent, and allow the player to move around the planet faster.
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