Intrude is a first-person shooter. Your mission is to get into a long time abandoned base, suddenly taken over by some kind of private military, find your way up and destroy the source of a signal comming from the base. Collect as much data as you can to find out what they are up to.
There are 5 big levels. More game design features, i hope you like it.
These levels are cool. In one of the levels, the exit is near the start and in order to play the level itself, you need to open a secret. It's great! Wolfenstein 3D also had something like that.