Aliens TC 1.0

Back in 94, mods were pretty much an open book. Almost nobody even thought about its full potential. However, one man named Justin Fisher released a full conversion mod that turned DOOM into an Aliens experience, and it changed the game industry forever. Even though he released almost nothing since then, he forced people to consider the legality and potential of mods. This famous mod is called Aliens TC.

Installing Aliens TC is simple. You need to have ZDoom and move the WAD file into the GZDoom folder, which is pretty par for the course for DOOM maps. 

The first thing you'll notice is that if you're a giant fan of the series, there will be a ton of recognizable locales. If you aren't a fan, they will likely fly over your head. In terms of gameplay, it is more survival horror than it is a nonstop action game unlike the original DOOM. Ammo management, aliens popping out of the walls that burst into acid when killed, and tons of crawling through air ducts.

Exploration is mandatory for your survival. If you don't explore, you simply won't have the resources you'll need to live. As far as actual gameplay changes go, the weapons have new sprites but fundamentally remain the same. They're all pretty useful except for the grenade launcher, as most of the fights are in close quarters.

All in all, this is a well-known mod for a reason. If you want to experience a tiny bit of history, then you should give Aliens TC a download.