Hard to believe that it’s been 25 years since id Software took the world of video games by storm with DOOM. Of course, after DOOM took over every network in every school and office, everyone and their grandma tried to capitalize on the first-person shooter genre. Dozens of DOOM clones (as they were known by back then) hit the market in the mid-90s. Some were able to carve out their own niche, while others are now best left collecting dust in your closet.

Really, you can’t have DOOM without DOOM clones. So, here are some of the famous, infamous and just plain weird first-person shooters to come out in the genre’s early days.

And just as a preface, this list doesn’t include Strife, Hexen or Duke Nukem 3D, since everyone includes those ones.

PO’ed – Panasonic 3DO, Sony PlayStation (1995, 1996)

Originally appearing on Panasonic’s 3DO before being ported to the PlayStation the following year, Any Channel’s PO’ed cast you as Ox, the cook of the military starship U.S.S. Pompous. The ship has been captured by aliens, which have killed all of the crew. That’s bound to make anyone a little…angry.

The game is pretty surreal in a couple of ways. For one, its sense of humor is apparent from the moment you start a new game with its difficulty settings being labeled with sly remarks (“I Like To Watch” is the easiest difficulty) reminiscent of Wolfenstein 3D‘s difficulty selection. From there, the sprawling 3D mazes that pass for the game’s levels are massive and feature plenty of platforming and moving parts. Then there are the over-the-top enemies, which are a mish-mash of creatures, including “Butthead”, a walking butt that shoots fart clouds.

Your arsenal includes a frying pan that gets stronger the more you’re damaged (aka the more PO’ed you are), a meat cleaver, a rocket launcher that fires manually-guided missiles, the Drill, which provides appropriate splatter on your screen, and your resident BFG clone, the Pulse Gun. You can also acquire a jetpack, which is not only used to reach higher areas, but can also get you out of a jam when swarmed by enemies. You also have a pretty useful 3D map that you can rotate and zoom in and out to better determine where to go.

Despite all these cool and funny components, not everyone will enjoy the bizarre humor, which can get a bit thin after a while. There’s also no music to be found in the game, which makes slog through long stretches of the game more boring than they need to be. Lastly, the controls aren’t as tight when compared to DOOM. Ox turns rather slowly, and can end up costing you if an enemy attacks from behind. It’s a one-note game, but worth checking out if you enjoy this weird brand of funny.

Marathon – Mac OS (1994)

Before they hit it big with Halo, Bungie had one of its first big hits on the Macintosh. Unlike many first-person shooters at the time (and even now), Marathon focused on story as well as gameplay. You play as an unnamed security guard aboard the UESC Marathon, a large Earth colony ship that has arrived in the Tau Ceti system to support the colony on its fourth planet. Aliens have attacked the ship, and it’s up to you to battle back.

Taking a cue from System Shock (I should say that System Shock took its cue from Marathon), the story is revealed via crew logs, historical documents, and conversations with the AIs that are onboard the ship via the computer terminals. Seen as the “DOOM killer” for the Macintosh, because of the fact that it was, well, on the Mac, meant it never got the exposure that it deserved. The game still got Bungie noticed by Microsoft, who needed a killer app for their Xbox…

If you are interested in checking out Marathon, Bungie has given the blessing to Aleph One, a Marathon open source engine that allows PC, Linux and MacOS users to play the original Marathon Trilogy for free.

Terminator: Future Shock – MS-DOS (1995)

After two so-so entries using their Terminator license, Bethesda struck gold with Future Shock. Future Shock is one of the first first-person shooter games to feature fully texture-mapped 3D environments and enemies, as well as using the mouse to look around. You play as an escapee of an extermination camp who becomes enlisted in the resistance by John Connor to help in the war effort. Throughout the game, you’ll be tasked with doing missions for the resistance, some of which involve driving a jeep or piloting a helicopter.

Apart from featuring characters from the films, the game also puts in fanservice for the music, weapons, enemies, and locales (Tech Noir!). In addition to the mouselook, the controls are also more akin to modern FPS schemes. The only shortcoming for the game is the level design, which is due in part to the limitations at the time. Many objects and buildings repeat themselves throughout levels, which can lead you to become lost if you’re not aware of your objectives. And then there’s that lack of multiplayer, which was rectified in the sequel, Skynet, a year later.

Chex Quest – MS-DOS (1996)

Yeah, this definitely fits the “weird” category. Essentially a total conversion of DOOM, Chex Quest was developed by Digital Café, and included as a pack-in promotion for Chex cereal. The game was not an entire reskinning of DOOM, as only the first five levels of the first episode were given a much less violent makeover. You can, however, still find the Ultimate DOOM WAD on the CD in the “Leftovers” directory, and you can access E1M6 through E4M9 via level warp codes. The story for the game has Fred Chexter, the Chex Warrior, sent to eradicate the invasion of the planet Bazoik by the Flemoids, a race of slimy creatures that threaten to upset the balance of breakfast and peace. The only way to stop the Flemoids is to utilize “zorchers” to send them back to their own dimension.

Not surprisingly, the game is a stark contrast to DOOM‘s ultra violence. All of the textures, enemies, weapons, etc. have been given a kid-friendly reskin. Flemoids will attack by sliming you, but don’t actually kill you. Likewise, you don’t actually kill the Flemoids, but your weapons will merely “zorch” them until they teleport back to their original dimension. In keeping with the idea of “healthy eating”, all health pack and potions are glasses of water, fruit and veggies, with the Soul Sphere being replaced by a breakfast plate (with Chex!). The game did the trick for Ralston Foods, and translated into increased sales for Chex cereal.

Isle of the Dead – MS-DOS (1993)

Coming out the same year as DOOM, Rainmaker Software’s effort is more Wolfenstein 3D than DOOM, but it paled in trying to come even close to either one. Combining point-and-click adventure gaming with first-person shooter elements, the game puts you as the lone survivor of a plane crash stranded on a mysterious tropical island that just so happens to be full of zombies being led by a mad scientist.

Straightforward but thin premise aside, the gameplay is anything but enjoyable. In spite of the included map screen, the map only shows the immediate area, with no indication of where the exits were, making the feature useless. The point-and-click segments amount to little more than pixel hunting on poorly-detailed screens. Furthermore, if you miss one of the items integral to progressing, you put yourself in an unwinnable situation.

Graphically, Isle of the Dead looked dated when compared to DOOM, feeling more like Wolf3D with its bland, same-y corridors, with poorly-detailed enemies. The enemies themselves don’t have any ranged attacks, and instead just line up for you to mow down, which isn’t much fun when you can’t even tell if you’re damaging them, thanks to the lack of animation.

The only real reason to play Isle of the Dead is for the numerous over-the-top death animations your character goes through. Sure, seeing your character being munched on by zombies in bad EC Comics style cutscenes is fun, but even they get old pretty fast.

Killing Time – Panasonic 3DO, Windows, Mac OS (1995, 1996, 1997)

Another 3DO exclusive that was later ported to other platforms, Studio 3DO’s Killing Time’s notable aspect is the use of FMV cutscenes performed by live actors, as well as their use in gameplay to reveal story elements. A year after the release on the 3DO, development was handed to Logicware, who redid much of the game for the PC release.

In Killing Time, you are an ex-Egyptology student out to investigate the mystery behind the disappearance of heiress Tess Conway on Matinicus Island, who just so happened to have inherited an ancient Egyptian water clock that supposedly granted immortality. The story goes that after a party with her other wealthy socialite friends, everyone disappeared. It seems that Tess’ dabbling with the water clock caused the island to become trapped in an eternal time flux, where the spirits of the residents of the island are doomed to spend eternity.

As mentioned, throughout the game, FMV cutscenes of live actors have been integrated into gameplay will play to reveal story elements. You can skip them if you wish, but you can always return to them if you missed a conversation. Gameplay-wise, the game incorporates puzzles in its Wolfenstein 3D-like levels that are labyrinthine in their design. Luckily, your overhead map does a good job of keeping your bearings. The enemies are a varied bunch, from undead bootleggers and clowns, the estate chefs that toss cleavers at you, to two-headed poodles.

Despite the atmosphere and design, the game was overlooked mainly because it came out on the 3DO, which was never going to cut it as a serious competitor to Sony, Sega or Nintendo. The action was also on the clunky side, which when compared to DOOM, wasn’t going to cut it. The PC ports didn’t fare much better, because again, that missing multiplayer component.

Disruptor – Sony PlayStation (1996)

Long before Insomniac Games gave us the Ratchet & Clank and Spyro The Dragon series, they had Disruptor, which was originally being developed for the 3DO, but development turned to the PlayStation not long after. The game’s cheesy cutscenes are indicative of the game’s 3DO origins, but despite that, the game is actually quite good for a console shooter at the time.

In Disruptor, players take control of new LightStormer Corps recruit Jack Curtis, who is also equipped with an implant that provides him with psionic abilities. Throughout the game, you’ll work your way up through the ranks while combating alien invaders, and eventuall,y uncover a conspiracy involving the presidency of Earth’s United Nations.

The psionic abilities are the big draw for Disruptor. As you progress through the game’s missions, you’ll acquire new abilities, such as a personal shield, an electrical shock or the ability to heal yourself. Coupled with a solid 30fps, varied level design that exude atmosphere, excellent graphics and control (despite the short draw distance in the outdoor areas), and a suitable array of weapons, Disruptor shows off the early brilliance of the Insomniac team. If it only wasn’t for those cheesy-as-hell cutscenes, which aren’t even in the “so bad it’s funny” realm.

Zero Tolerance – Sega Genesis (1994)

You read that right. The Sega Genesis (not the 32X, guys) had an actual first person shooter. Two of ’em, actually (three if you count that unlicensed Duke Nukem 3D “port”). Given the limitations of the Genesis, Zero Tolerance was quite an accomplishment. The game even had link cable support for two people to link their consoles together to play co-op multiplayer.

In the future, mankind has taken to colonizing the rest of the solar system. These colonies are protected by the Planet Defense Corps. However, when Europa-1, one of the main ships of the Planet Defense Corps, is attacked by an unknown extraterrestrial force, Zero Tolerance is called into action. As a member of the elite squad of five commandos, each with different abilities, the player is tasked with infiltrating the ship, eliminating the alien aggressors and cleaning things up.

Consisting of 40 levels spread across three areas, Zero Tolerance puts you on the clock from the get-go, as the aliens have damaged the ship’s nuclear cooling system, leaving you only a few hours before the ship explodes. The objective for each level is to all of the enemies, and then proceed to the exit. Belying the Genesis hardware, Zero Tolerance runs fairly well (though there is some choppiness to the graphics), and features digitized voices with pretty good sound effects. However, the slow turning speed, massive pushback from being hit, and limited view (think looking through a cardboard box) can make the game a frustrating affair, unless you use your map to properly line your character up with the approaching enemies.

Star Wars: Dark Forces – MS-DOS and Mac OS, Sony PlayStation (1995, 1996)

Lucasarts got on the DOOM bandwagon with their own first-person shooter set in the Star Wars universe. Using the Jedi engine, Dark Forces differentiated from DOOM with its varied movement mechanics (including the ability to look up and down), multi-floored level designs, atmospheric effects such as fog and haze, animated textures, and employ the use of 3D objects. Dark Forces still used 2D sprites for enemies and items, however.

The game uses an original story set in the Star Wars universe, revolving around Kyle Katarn, a mercenary employed by the Rebel Alliance to stop the Empire from mass developing a new version of Stormtrooper called the Dark Trooper. Dark Forces featured locations, characters and enemies from the original trilogy, including an appearance by a certain bounty hunter. Weapons included Katarn’s Bryar Pistol and Stormtrooper rifle, as well as I.M. Mines, Thermal Detonators, and even a grenade launcher weapon in the Packered Mortar Gun.

Despite lacking that multiplayer component (and the ability to wield a lightsaber or The Force), Dark Forces maintained a strong following in the early days of the internet, with numerous mods and level packs. The lack of a lightsaber, Force powers and multiplayer were addressed in the sequel years later in Jedi Knight: Dark Forces II.

Rise of the Triad: The Dark War – MS-DOS (1995)

Who knew that the one game that could possibly rival DOOM would come from one of its own? Developed by Apogee Software with ex-id Software designer Tom Hall, Rise of the Triad started out as a sequel to Wolfenstein 3D, but eventually morphed into something else entirely. While the game incorporated a multiplayer component, as well as a few revolutionary technical features, it couldn’t stop the DOOM juggernaut.

Being that the game had begun as a Wolf3D sequel, the story would have involved BJ Blazkowicz going up against an evil organization known as The Triad, which had been behind Hitler’s world domination plans all along. When that was dropped, the story became The Triad having plans to destroy Los Angeles. A group of special ops known as The HUNT (High-Risk United Nations Task-force) are sent in to investigate the cult’s base of operations on an island off the California coast. They’re of course discovered, and their boat is blown to pieces. Left with no other choice, the HUNT team begins the task of stopping the cult and their leader, El Oscuro.

Despite the game running on the Wolf3D engine, ROTT offers a lot of enhancements. For starters, you are able to select one of the five HUNT members at the start of the game, with each having different stats. Secondly, the graphics received a big upgrade with the digitized actors and textured environments, though it wasn’t as varied as DOOM. Thirdly, you had more movement in the form of jump pads, which allowed you to get up to higher platforms, though again, the levels themselves were still linear like Wolf3D.

Probably the best thing about ROTT is the fact that unlike DOOM, it just didn’t take itself seriously. This results in the aforementioned jump pads, wacky weapons (like the drunk missile or flamewall), kooky bosses (Sebastian “Doyle” Krist’s “Bleh!”), ridiculous power-ups (who doesn’t love Dog Mode?) and ludicrous gibs. Seriously, if you timed it right, you could grab a screenshot of an exploded enemy’s severed hand flipping you off amidst the eyeballs, skull and guts flying around. It was really over the top, which was all part of the fun! ROTT also had a multiplayer component, with nine different modes (including a “Capture The Triad” mode). It even had mic support! The game was so well loved that it got a 2013 remake, which while not nearly as good, kept a lot of the zaniness that set it apart from DOOM.