'Troids is an update of the classic arcade game Asteroids.
Take control of a triangular spacecraft with a single weapon. You can rotate the craft left or right, and maneuver using the thrust button. If any asteroids or alien weapons touch you, it's instant, explosive, death, and everything must be destroyed before you can proceed to the next level.
There are some nice touches in 'Troids. Unlike the original, instead of the edges wrapping around, the arena in 'Troids is closed and asteroids and projectiles bounce of the sides. This makes asteroid movement a bit more dynamic, and also allows you to deflect fire off the walls.
There are also more challenging enemies in 'Troids. From giant rotating laser beams, to Chinese dragon-like enemies that fill the screen with bullets. This makes 'Troids much more interesting, but also pretty hard.
The difficulty is the main problem with 'Troids, because there is no save game, so every time you run out of lives it's back to the start! This is a very traditional approach, but it can be frustrating. There is also no windowed mode.
'Troids is a cool modern update on a gaming standard. It looks and sounds great, while being a real challenge.