Recent reports confirmed that the aliens started invasion to our galaxy. We will have to send all our soldiers and confront them. According to unverified reports, we have the best chance, if we face them on Mars, we should have strategic advantage there. But Mars is not the only place, where the war will be unleashed, it is certain now.

Instructions

*WASD* - move
*down*, *up*, *left*, *right* or *arrows* - move
*mouse* - look around
*space* - jump
*shift* - run
*0*..*9* - change guns