4D Golden Eye

The tessearact (see link) is a 4-Dimentsional analog of a 3-dimensional cube. Computers can calculate their properties and simulate them. As creatures who natively understand 3-dimensional geometry, we can only understand 4-dimensional objects through their projection into 3-D space.

This game is a first-person shooter ala Golden Eye, where you play a 3-D person running around in a 4-D building. Each room is a hypercube, hyper-rectangle, etc.

It's a challenge at first, trying to chase, shoot, and sneak up on your enemy, but over time, with trial and error, you will develop a sense of 4-dimensional projections well enough to play competitively.