Tower of Heaven is a retro-style platformer with black and green color palette reminiscent of GameBoy games and a chiptune soundtrack.
You play as a lone traveler trying to ascend the Tower of Heaven despite the will of a spiteful deity residing at the top of the world. There are no enemies, but the levels are full of obstacles like spikes or buzz-saws which you need to overcome by careful jumping. Each level is timed. To make things harder as you ascend the deity introduces new rules, like "you can't touch golden blocks" or "you can't go left".
Browser version features some additions to the original Windows game:
A new secret area;
Extended ending for finding all secrets;
Additional music, sounds, and graphics;
Various gameplay / graphical fixes;
Level creator that lets the players make and import custom levels.