Prey (video game)/WMG

Prey and Turok are set in the same universe
Look at all the similarities, native American heroes, strange alien worlds, portals jumping you between locations, strange guns, mythical abilities...

Hell even the Sequel Hook at the end of Prey kinda fit into this.

Duke Nukem Forever will tell the same story as Prey, from a different point of view
Evidence #1: several Prey monsters are very similar to Duke Nukem monsters
 * Hunters are reptilian humanoids with weak guns, like assault troopers
 * Harvesters with jetpacks fly around and shoot rockets, like assault commanders
 * Hounds are monstruous bipedal beasts that scratch their enemies, like protector drones
 * Gasbags are tentacled flying creatures with multiple eyes, like octabrains
 * Mutates are former humans mutated by the aliens, like pigcops
 * Drones are flying robots that even share the same name with sentry drones

Evidence #2: some weapons in Prey are very similar to what we saw or read in several trailers and documents of Duke Nukem Forever
 * The launcher in Prey uses organic ammo, like the shrinker that was shown in the 2001 trailer of DNF
 * A weapon in Prey is a crab-like creature that is used by ripping off one of its legs and throwing the rest, just like Duke has been shown to do in the 2001 trailer of DNF
 * The leech gun in Prey can use freeze ammo, effectively becoming a freezethrower like the one Duke Nukem uses
 * The 1997 preview of DNF in PC Gamer mentions boots that will "allow Duke to walk on metallic walls and ceilings", like the wallwalks allow Tommy to do in Prey
 * The leaked DNF world chart mentions a level based on changes in gravity, which have been massively present in Prey

Evidence #3: the two games are set in the same dates
 * According to the leaked world chart, the events in Duke Nukem Forever start on "Saturday, April 1". The last time April 1 fell on a Saturday was 2006, the year Prey was released and probably when its story takes place

This would also explain why Tommy is so reluctant to be a hero, even after he acquired the power to return to life at will. He is just thinking: "Why should I do this? Duke Nukem is gonna save the Earth like he always does, before I even try!"

The Keepers Of The Sphere Lied About Seeding The Earth With Life...
The beings Tommy is about to meet with are the ones who actually seed worlds with life and they seek to employ him in an effort to thwart similar poachers throughout the galaxy.