The series only consists of two games. The first one is available for the Neo Geo, Sega Genesis and SNES which has a wrestling game complete with energy "ropes", in which the goal is to pin down your opponent for a three count. Tanks, helicopters, and maser cannons also periodically attacked during the matches.
The second game was available for the Neo Geo, SNES and Genesis. The game play of the first two is a side scrolling, cooperative Beat 'em Up while the Genesis version featured a tournament like fighting game in which you must defeat every monster in the game one by one in order to reach the boss at the end, YOURSELF.
The first game features six characters:
- Geon: A giant dinosaur (no monster brawler is complete without a giant reptile of some sort)
- Woo: King Kong's cousin
- Poison Ghost: A monster covered in toxic waste
- Rocky: A giant golem
- Astro Guy: A giant humanoid superhero
- Beetle Mania: A large beetle-like creature, suggested to be an alien.
Woo and Poison Ghost aren't in the SNES and Genesis ports. Additionally, Poison Ghost, Rocky, and Beetle Mania are not in the sequel — the remaining three are now powered-up versions of themselves, joined by the new boss characters for a total of 10 playable monsters. The listed names are from the US/European version, with the names from the Japanese version in parentheses.
- Aqua Slug (Sack Eyes): A giant slug who is nigh-invulnerable while withdrawn into its shell.
- Eiffelyte (Horn du Out): A giant human with an orange blob attached to his head.
- Huge Frogger (Huge Keal): A giant space-helmet-wearing humanoid frog-like creature. Underneath its helmet is actually a fish's head.
- Claw Head (Yam a Mordon): A large green monster with two heads that has a big horn on each. It also has large mouth on its belly and uses its arms to walk.
- Lavicus (Eat Wow): A blue monster with a big severed mouth and a small serpentine body. it has bat like wings on the back of its head, an odd tube with sharp teeth on his forehead, three eyes and long skinny arms. It also has a large eyeball inside his severed mouth.
- Beetle Master (Kili Kili): A large scorpion monster with four legs, an eye on his belly and a sideways mouth between his legs. His brain also shows but it's protected by a helmet.
- Famardy (King Famardy): A gigantic green blob with four eyes, lots of teeth and an orange head sticking out of its mouth. It also has arms sticking out of its midsection. He is not playable in the Genesis version.
- Atomic Guy: A powered up version of Astro Guy
- Super Geon: A mutated spiky form of the previous Geon.
- Cyber Woo: Behold, a giant robot King Kong!
These three are the heroes of the series.
Despite the name, this has no direct relation to Godzilla: King of the Monsters! or anything else in the Godzilla franchise (aside from a Not Zilla). Also not to be confused with War of the Monsters, which shares similar themes.
This series provides examples of:
- Balloon Belly: Aqua Slug can turn its foes into parade balloons by blowing odd glops of goop at them.
- Strangely, the victim does not pop. They would just appear back to their normal size and falls down.
- Body Horror: Pretty much all of the characters.
- Boss Game: The sequel.
- Captain Ersatz: Nearly everyone.
- The Computer Is a Cheating Bastard: The computer-controlled monsters have all the advantages. You get one free "power struggle" and then can forget about winning any more against that opponent.
- Crossover: Cyber Woo made the cut for NeoGeo Battle Coliseum. Also, Atomic Guy can be summoned in one of Yuki's special attacks.
- Deadline News: The ending of the first game.
- Divergent Character Evolution: The six monsters in the first game had the same movelist, with the only difference being what their projectile attack is and how they did certain moves. The three returning characters in the sequel have much more unique normals and specials.
- Eldritch Abomination: Famardy, plus several of the weirder monsters such as Lavicus. Many of the disembodied heads and eyes that serve as minor mooks might also qualify.
- Speaking of Famardy, if there's still any doubts about him, check out the Game Over screen of the second game◊. Yep, that's him. Good luck sleeping tonight.
- Large and in Charge: Even considering all the characters are kaiju, Famardy is still larger than them all, and is one of the largest characters to ever appear in a fighting game.
- Mirror Boss: How awesome is it to fight your clone?
- Nintendo Hard: Neither game is exactly easy, but the original Neo Geo version of the sequel is perhaps one of the most brutal, unrelenting and merciless quarter-munchers ever made. Gaming Hell sums it ups pretty well.
- Player Versus Player
- Sequel Hook: The ending of the sequel clumsily states that "In 800 years, a few survivors will have power."
- SNK Boss: Well, the games were created by SNK.
- Spiritual Successor: Godzilla Domination for GBA is very clearly modeled on this series — with most of the cheating elements and the Scrappy Mechanic removed. It's a Cult Classic.
- Stuff Blowing Up
- With Great Power Comes Great Insanity: Astro Guy was a brilliant scientist until the experiment that transformed him. Now his intellect is fading, replaced by his now-monstrous instincts. As Atomic Guy, he has nothing left but an overpowering hunger for nuclear energy.