There are very big bads as iconic as the King of all Koopas. Bowser has been a thorn in the Mario Bros. side for decades now and he's even managed to make cameo appearances in other games and films. You'd be hard-pressed to find any gamer that isn't at least aware of who Bowser is. He's large, in charge, and pretty consistent as far as villains go. He hasn't changed much in recent years and he seems to always have the same plans of domination in mind (when he's not pining over Princess Peach).

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Back when Super Mario Bros. was just starting to gain fame, Bowser was a very different creature. In fact, he went through tons of changes and saw some insanely weird variations pop up here and there. Here's a glimpse at 10 of the strangest variations of Bowser we've seen so far!

10 Bowser's Original Sprite (Super Mario Bros.)

Some of Bowser's weirdest forms stem from older pieces of concept art or sprites. It's no surprise to many gamers that the machines and consoles of yesteryear weren't exactly as "capable" of producing amazing graphics and top-notch sprite-work as they are today.

Nintendo still managed to piece together a colorful and much-beloved NES title with Super Mario Bros. but the sprite of Bowser that appeared at the end of each Word Castle looks absolutely nothing like the iconic big-bad we see today. Thanks to restraints, the boss is a cobbled-together version of what was on hand with the end result looking more like 2D nightmare fuel than King Koopa.

9 Bowser's Brother (Super Mario Bros.: The Lost Levels)

Many players were shocked to learn that the Koopalings that did Bowser's bidding in Super Mario Bros. 3 were not actually related to the Koopa King himself. Many assumed they were his children but Nintendo was quick to squash the rumor.

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However, that doesn't mean Bowser is completely without family. You can actually find "Bowser's Brother" in Super Mario Bros.: The Lost Levels. The revamped NES title showcases a curious Bowser sprite that is blue/teal-skinned with a brown shell. He's identical to his big brother

8 Bowletta (Mario & Luigi: Superstar Saga)

Bowser always seems to be involved when villainy springs upon the Mushroom Kingdom, even if he's an "innocent bystander." There have been a couple of Mario events in which King Koopa wasn't pestering the masses of his own free will (although given the chance, we're convinced he'd go along with it anyway or even welcome it).

Mario & Luigi: Superstar Saga introduced players to the dastardly Cackletta, a Beanish with sinister motives involving Princess Peach's voice. As the game progresses, Cackletta finds a home in Bowser's body, transforming our much-despised villain into a freakish version of himself with wide spiraling green eyes and a sinister smile.

7 Bowser Who? (Mario Is Missing!)

Mario Is Missing! is definitely a black sheep when it comes to the Super Mario Bros. franchise. The educational adventure wasn't well-received by fans and there was quite a bit of variance between the NES, SNES, and PC versions.

The PC version received a lot of hate but one of the most curious blunders comes from the NES variant. The team that developed the title had apparently never seen Bowser and was simply going off "things they'd heard about the office" when compiling his sprite. This version of Bowser looks nothing like the King Koopa we know and the "final boss" fight against him is downright disrespectful to the character.

6 Armored Bowser (Yoshi's Safari)

What's that? You've never heard of Yoshi's Safari? If not, no worries, you aren't alone. This is definitely one of the most obscure Super Mario Bros. titles floating around. The main reason for its rarity stems from the fact that it was one of the few games to make use of the SNES Super Scope.

The rail-shooter featured some familiar faces with Yoshi as the main character but the final boss-battle introduced us to a unique Bowser that was decked out in some type of futuristic armor. The entire outfit had the Koopa King looking like a Space-faring Knight complete with arm blasters. Once the armor is blasted free we see the Bowser we all know and love but the initial reveal is pretty strange.

5 Bowser K. Rool? (The Super Mario Bros. Super Show!)

Back during their introduction, the Super Mario Bros. became such a tour-de-force that they kicked up a whirlwind of intellectual properties and merchandise. Not only did the duo spawn a horrible live-action movie but they also managed to inspire a variety of cartoon shows and commercials. One of their most "successful" was The Super Mario. Bros Super Show! which featured a blend of live-action skits and cartoon shorts.

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The Bowser in this television variation looked much more like a dinosaur or a prehistoric lizard than a Koopa, at least from the front, and much like a Scooby-Doo villain, he would be seen swapping costumes between episodes. One outfit saw him looking extra Piratey and a bit like King K. Rool of Donkey Kong fame.

4 Bowser's Earliest Concept (Super Mario Bros.)

Characters go through a ton of changes and phases during the development process. Whether it's for books, films, or video games, you can bet that many of the characters you see were very different during their inception.

Bowser was no different. The King Koopa we all know and love to hate is a muscular behemoth that sports a razor-sharp spined turtle shell and some very domineering features. In his earliest stages of development, however, Bowser looked a lot goofier. He looked more like a slightly angrier Koopa Troopa than their big bad boss.

3 You Cannot Beat Us (Commercial)

Sometimes, the creative minds behind commercials can go a bit off the rails. This is exactly what happened for Nintendo when they aired an infamous commercial referred to as "you cannot beat us" back in the late 80s. For some reason, the creators thought it would be a great idea to use stiff-moving and awkwardly smooth 3D rendering to get their message across to players.

The end result showcases the original NES Bowser looking even creepier than normal with Lego-like teeth and an almost un-hinged lower jaw.

2 The Human-Side Of Bowser (Super Mario Bros. Movie)

There are quite a few video game and film fanatics out there that subscribe to the idea that the Super Mario Bros. film simply never happened. Unfortunately for them (and most of the general public), the movie is very real and VERY strange. The live-action aesthetic simply doesn't work for the whimsical world that Nintendo aspired to build and the enemies that the brothers must face are like the product of some sort of cough-syrup-induced fever dream.

King Koopa himself is exceptionally weird even if he's played by the exceptionally talented Dennis Hopper. No amount of solid acting could save the world from the prospect of a half-human half-Koopa. Even Hopper's eventual transformation is more akin to something out of John Carpenter's The Thing than anything Nintendo would produce.

1 King Koopa (King Koopa's Kool Kartoons)

What's the easiest way to make Bowser look as absolutely strange as possible? Simple, turn him into a late-80s live-action icon. For a little bit, Bowser had his own television show (like the Super Mario Bros. Super Show!). King Koopa's Kool Kartoons was a strange premise all its own but the real oddity was the King himself. There is something supremely creepy about "Bowser's" design here. It's all too uncanny if you ask us.

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