Icarus: Alien Vanguard

Icarus: Alien Vanguard (ICARUS.WAD) is a 32-level megawad released in 1996 by TeamTNT. It was developed as the collective's first freeware release, after TNT: Evilution was picked up for publishing by id Software for what would become Final Doom. The first level sees the player commandeering a shuttle and flying it to the infested exploration cruiser, the Icarus. From there, the player must fight through the ship, regions of the neighboring planet, and unsafe simulations to cleanse the demonic threat. A sequel, Daedalus: Alien Defense, was released in 2003.