• The bio-weapon in question is called "Gamma Class Bio-Weapon, project no. 154." He is being held in the genetics division of Systems Corp., in a padded containment cell with "318" stained onto the wall. He waits to have his abilities evaluated while a doctor prepares his medication: muscle enhancers, behavioral suppressants, mind controllers, and genetic purificants among them. While imprisoned, they repeatedly test him for effectiveness and perfect him. His sole purpose: to kill. He can't live this way. He must be free. He must escape. He overwhelms the doctor, kills him, and takes his weapon, a pistol. He shoots out a vent in the ceiling and climbs to his escape. He takes out several underpowered guards and (interestingly) fights in some darkening rooms until he is met with "Posideon," one of Systems Corp's elite weapons. Posideon is an "Alpha Class Bio-Android" with jet boots and an advanced laser weapon, with some kind of blade attached. Posideon is killed, and explodes (albeit with skimped explosions). 154 escapes to freedom.
• He meets fresh air for the first time, and discovers his captors' name: Systems Corp, and their slogan, "Innovating Life." He also discovers his right to live a real life, not one dedicated to combat. 154 gets past more guards and the "Government Research Terminal #435345" announcing his escape and manhunt. Then, an odd scene: Poseidon appears again, motionless and bloodied, atop a bunker. Gunshots don't appear in this scene. 154 "examines" it, and a cutscene plays. Poseidon rises, and strikes quickly at an unclothed and weaponless 154. The screen blacks out, and the entire game completely resets.
• Thing Thing 2 begins with 154 back in the city, battling even more enemies. Completely unarmed and slow, but more. Seriously, you'd have to be playing while unconcious to die at this point. 154 is still under pursuit by countless mercernaries who chase him to the desert. Here, "mummies" (courtesy of Systems Corp.'s reanimation experiments) emerge from catacombs to attack 154. The only difference in fighting experience is that they have more life. Yep.
• Eventually, 154 makes it back to the industrial sector and meets the second bio-weapon out to end his life, "Zues." Zues is a much more effective enemy than Posideon or all the other enemies in TT2 put together, and comes complete with black, spiky, badass armor, a skeleton-like appearance, and a gun the size of a small car. Loud thunder n' lightnin' (that can't be turned off) crashes the entire battle; how appropriate while fighting Zues. His high-powered rifle does massive damage, and mobbing mercernaries don't help. After a long battle, Zues is struck down, and explodes. 154, finally able to rest, goes into hiding. An abrupt end to an otherwise flawed game.
• Thing Thing 3 begins, and 154 comes out of hiding after receiving a message from an unknown individual who is aware of his origins. 154 follows the individual's instructions, taking him to Sunset City, a housing development for Systems Corp. employees. There, he meets his contact: Bio-Weapon, Project no. 153. 153 was designed as an advanced pilot, with the gift of being completely aware of his surroundings. He explains 154's original purpose and resistance to hydrostatic shock, allowing him to rapidly heal and suffer immense amounts of damage with little to no effect to his fighting ability, thus making him the perfect soldier. Unfortunately, 153 has lured 154 into a trap. It's bio-weapon versus bio-weapon as 154 takes on 153's powered armor suit and shotgun. 153 is defeated, and his suit destroyed, but he lives to send 154 into a secret, ice-encrusted Systems Corp. service tunnel. 154 fights through even more mercernaries back to the top, only to be cornered by 153 again — this time, cast into a biowaste disposal facility. If the site where the rejected remains of failed genetic experiments were left to rot and gooify wasn't bad enough, 153 left one last surprise: the reanimated prototype of the Hades project, Vahl Dreig. Vahl is the largest enemy 154 has ever faced. It is a 25-foot/8-meter tall dragonlike creature with many mechanized parts. Although it has tattered wings, it makes no attempt to fly. It can fire a powerful, large beam from its mouth and swipe with its long claws. It can only be hurt in the head, as all the other fleshy parts are encased in machinery. 154 prevails over defeating the creature, but realizes he's still trapped in the previously described biowaste chamber. Damn.
• Thing Thing 4 picks up right where TT3 left off, and, after a nice clip show of the last 3 games, 154 reminds himself of his mission. He (bloodily) removes the energy core that powered the Hades prototype, comments on its explosive tendencies while tossing it up in the air, and throws it against the steel-reinforced chamber wall. The ensuing explosion tears a large crater in the wall, and 154 climbs through. (Warning, kids: don't throw explosives at walls. Or at anything. Why do you have explosives anyways? Kids these days… And if you failed to heed that warning, don't climb onto the freshly exploded wall. It's probably hot/acidic. Failure to heed that may result in ohmyGodmyhands syndrome.)
• Now in the biowaste incinerators, 154 fights past legions of trained soldiers who arrive via handy-dandy teleporters. He escapes into the offices, determined to take out the Systems Corp. management and end it all. However, 153 is back, along with a squad of soldiers. 154 escapes by defenestrating himself. He lands on a car parked outside with such force that the entire engine block is extricated. 154 commandeers a nearby sports car containing an oh-so-convenient HK21 machine gun. 153 is in pursuit in a large helicopter, raining bombs and Vulcan cannon shells onto 154. Eventually, the fuel tank is shot enough hundreds of times that the helicopter crashes, and 153 is presumed dead. Freaking finally.
• 154 goes to Systems Corp's genetic research laboratory in hopes of finding the CEO. There, he discovers the full potential of Systems Corp's human arsenal, experimental efforts, and the scores of previous experiments before him. 154 then has the choice of fighting either ravenous zombies who swipe at his delicious innards, or the synthesized life form, Stinky Bean. Either choice locks you into a chamber with a near-infinite amount of organisms that make every other organism grateful of its divine design. After this horrible ordeal, 154 runs past the very suspended animation pod he was created in, alongside 153's, now empty, shattered, and wrapped in warning tape. Fighting through a heavily-defended quarantine elevator, 154 enters a room where a giant container releases his final opponent. 154 finally encounters Hades in the form of a slow-moving, dishevelled, and meek individual, capable only of weak melee attacks but with great physical endurance. Once seemingly dead, Hades collapses. The body twitches, then writhes. Long, mechanical, and spider-like limbs gorily emerge from Hades' body, lifting him 15 feet in the air. Armed with the powerful Hades Rifle and swiping legs, Hades' true form fights 154. 154 kills Hades, takes his weapon, and storms the final room. However, there he encounters only countless screens bearing the image of the CEO he came to kill, who reveals that 154 is but a clone in an army of millions. A gas is released, removing 154's ability to heal rapidly. The last soldiers left are thrown at 154. There, Gamma Class Bio-Weapon, Project no. 154 is shot dead, his remains scraped up and used to refine the genetic splicing process.
He will be perfect…
154 will live again…
Thing Thing is one of the greatest Internet games ever.