Dreadnaught

Wave survival stands on two things. Weapon feedback, and how the horde paths around you. Setting it on the moon is either the entire point or it's a skybox (first thing I'd go and check). The genre is understood well enough that there's no mystery about what good feels like here, so it makes for a fair test. I'd take that test.

Round based horde defence, and you know the deal inside twenty seconds. No story to sit through tho, which I appreciate. A scoreboard with zombies attached, and it doesn't pretend to be more.

Rebuilding a famous formula in a browser isn't ambition. To its credit, this makes no claim otherwise. Says space zombies, delivers space zombies. Whether that's enough rests entirely on how the shooting feels, and that's the risk of the whole approach. Even so, I'd take an honest version of a good shape over a clever idea nobody can play.

No surprises, and none promised either. Waves escalate, you buy things off the wall between them, you get a bit further each time. The space setting doesn't change much mechanically, but it looks good and the weapons have real weight. Straightforward, and honest about being straightforward.