Review: Gravitron 2

Gravitron 2 is a retro-style arcade shooter in the vein of Gravitar and Thrust. You fly a rocket to a series of tiny planet surfaces, where you must destroy one or more reactors and then make your escape before the entire planet blows up. In addition to flying and shooting, the ship is capable of landing on any flat surface, which is useful for rescuing engineers. Each rescued engineer repairs a bit of hull damage as well as adding a bonus to your score for the level.

The ship controls are a slight update to the Lunar Lander family. The mouse's X axis directly orients the ship, and there is a button each for thrusting, firing, and shields. Thrusting and shields expend fuel, which can be replenished by landing or hovering near fuel depots in the levels.

The game has a nice variety of enemies. Levels often contain moving parts. There are occasionally gates with switches, and destructible trees. Each level has a checkpoint; when you first touch the checkpoint, it snapshots the enemies alive at that time. When you die the game restarts you at the checkpoint with the snapshotted enemies. Thus there is an incentive to try and clear as big a swath of the level as possible before touching the checkpoint, which is risky.

I have not finished the game; I think I'm about twenty levels in. I don't think the difficulty curve is as smooth as it ought to be (I'm reviewing version 1.5). Gravitron 2 is brutally hard in places; I've played some levels dozens of times to get through. I have a dormant game project that uses almost this exact interface, so I was already quite good at flying the rocket, and it is still really hard for me. In general the game does a good job of encouraging “Just one more try” gameplay, though. My two-year-old daughter likes watching the game; when I die she tells me “We have to try again!”

I was just over at the Chipmunk physics library page and noticed the game author's handle in the forums, so I wouldn't be surprised if Gravitron 2 makes use of the Chipmunk library for its physics. In general the game's physics is impressive, but there does seem to be some inconsistency in how much damage collisions with the environment do. I also wish the rocket didn't bounce quite so much off of walls.

There's a free demo available with the first five levels. If you like it, the full game only costs $5 (at this writing) so it's not a difficult purchase to justify. In terms of hours of gameplay per dollar this is a great value.

Ron “X-Out” Bunce has since updated his game to version 1.7, fixing several minor interface quirks and an instant-death physics bug. Give it a try!