VVVVVV v2.2.0.3 GOG

Help! Everyone has been teleported away randomly! As the heroic Captain Viridian, it's up to you to find your friends, bring them back to safety, and save the universe!

VVVVVV is a platform game all about exploring one simple mechanical idea - what if you reversed gravity instead of jumping?

The game is designed not to artificially gate your progress. In VVVVVV there are no locks, no power-ups, no switches, nothing to stop you progressing except the challenges themselves.
Key features:
Elegant, minimalistic level design.
Challenging, fast and fun gameplay.
Frequent checkpoints mean you never have to replay challenges you've already beaten.
Over half an hour of chiptune music by composer Magnus Pålsson.
Special game modes, including time trials and a no death mode.