The video begins with a van dropping off Mario and his friends at a Roman Colosseum. It is revealed that SMG3 was the culprit behind their situation. His latest scheme was to have them fight each other in a battle to the death. Initially, they refused since they would never hurt each other for free, especially Luigi but after SMG3 offered a cash prize of $3, they accepted, allowing the battles to begin.
Mario hoped to have an easy fight. Frankie appeared and thought his wish was granted. This was proven false when Bowser dropped in and crushed Frankie, revealing himself to be the true contestant. Mario realized he was done for while SMG3 said that Bowser had an easy target. As Bowser charged with a mace, Mario easily dodged and took out a sword, just to be instantly destroyed by the mace, forcing Mario to run for it. As he got to the wall, he tried to talk it out with Bowser but it failed and he had to dodge the mace. He did so a few times but as he taunted Bowser for not being able to hit him at all, his head got hit by the mace, causing him to go around. As Bowser laughed, Mario became angry and used his fingers to poke his eyes, causing Bowser to yell in pain and let go of both him and his mace. As Bowser got back up, Mario quickly threw his shield to knock him back down and took the mace. Just as Bowser got back on his feet, he wondered where was Mario, just for the plumber to ambush him from the back and slammed the mace into his butt, sending him flying out of the Colosseum, much to the surprise of SMG3.
Wario and Waluigi entered the ring riding on horses and equipped with spears. Mario complained about not getting either, which SMG3 responded by throwing a shoe at him. Wario charged at Mario, who jumped over his horse and knocked his spear out of his hands. Wario suddenly got the idea of using Waluigi as his weapon and charged at Mario, who kicked the horse and made the duo crash into the other end of the ring. Enraged, Wario pulled out a remote and turned the horse into a yellow sports car, much to Mario's dismay. The duo then attempted to run down the Italian plumber with their new car, only for him to casually sidestep and send them on a collision course with the Colosseum walls.
Luigi begged his friends not to fight but to no avail. Toad charged at Mario, who simply picked him up and dropped him into the surrounding lava pit. Luigi performed a spin attack towards SMG4, who defected it back at Mario who did the same, resulting in a humorous scene in which the two repeatedly deflected Luigi as if it were a game of tennis. Eventually, Mario got tired of the foolish activity and let Luigi fall into the lava. SMG4 then struck Mario, leaving him dangling over the edge. Before SMG4 could knock him into the lava pit, Mario got the idea of lying to Old Man Hobo that SMG4 said he was "stinky". The old man promptly became savagely furious and beat SMG4 into a pulp before knocking him into the lava, much to Mario's enjoyment. Old Man Hobo celebrated what he did but it did not last long as Mario knocked him into the lava, making Mario the winner.
Mario was confused as to why there were no Teletubbies in the battleground. Suddenly, a large Trojan horse came down. SMG3 said that it was a peace treaty and a gift from the Teletubbies. Mario got excited, thinking that it was a giraffe, and climbed on it. What he did not know was that the Teletubbies were actually inside the horse, ready to ambush him. Of course, they did not expect Mario to jump about repeatedly on the horse. With his huge weight, it was only a matter of time before the wooden horse collapsed on them, killing them. Mario then thanked the Trojan horse for killing them, making Mario the winner.
This battle was a chariot race in a go-kart track due to SMG3 being unable to find an actual chariot course, as pointed out by Mario, although that only caused SMG3 to tell him to shut up. Bob said that he and Fishy Boopkins (where the Spike said yeah before realizing he was supposed to be an animal pulling the chariot and made a woof sound) were going to defeat Mario and Yoshi, Mario's steed pulling his chariot. During the race, Mario resorted to bumping Bob's chariot off the track, who complained he was not playing fair. Mario flipped him off, saying he did not care, just to have the Garo throw something at him. Meanwhile, Fishy Boopkins and Yoshi decided that they were tired of being pushed around and ditched Bob and Mario to watch anime and deal weapons respectively. That resulted in both Mario and Bob carrying their chariots to the finish line. Bob suddenly fell, allowing Mario to continue, making him the winner.
At first, the two fighters stared at each other. Then Steve opened a stone builder from Minecraft, and built an entire fort at impossible speed. Steve shot arrows at Mario, all of which missed their target. Mario, thinking it would be easy, charged. Suddenly, chickens with crossbows appeared and shot a flurry of arrows that left Mario injured. He ducked behind a pillar. He suddenly saw a rock and thinking quick, combined it with his clothes to make a decoy, fooling the chickens to shoot at it while he sneaked around the fort. As he got to the back, he found a secret door leading inside. He found Steve playing on his computer and attacked him, making Mario the winner.
Mario vs. SMG3
SMG3 revealed to Mario that he has proven to be quite the capable warrior, and wanted him to become his minion. Mario though did not listen and threw a rock at SMG3 for no reason. Angered, SMG3 gets on a chariot with guns and charges at Mario who did nothing. SMG3 stopped the chariot to ask why was he not attacking, just to be attacked.
Near SMG3's throne, Bob came carrying his chariot wondering where was the finish line. Suddenly, he saw the throne and proceeded to sit on it, commenting on how nice the view was from where he was. He then saw a button on the right arm of the throne and pressed it, curious to its effect. A rumbling sound could be heard and the two stopped fighting. SMG3 then angrily told Bob to stop pushing the button. However, Bob was too engrossed into pushing the button and released Simba from his cage. Both Mario and SMG3 found him cute. Then, Leomon, the Digimon "God of all beasts" appeared and proceeded to attack SMG3, who said he forgot about it. Bob then saw another button on the left arm of the throne and pressed it. A door opened revealing a room holding everyone who got eliminated from the tournament. SMG3 tried to pass it off as if no harm was done but they were not buying it. Subsequently, SMG3 could be seen hung upside down at Peach's Castle from his shoe being on fire and having several spears through his body.
The statue that SMG3 points out to "prove" that firearms existed during Ancient Rome is that of Augustus; a Roman statesman and military leader who was the first Emperor of the Roman Empire.
Shroomy only appears once in the video near the start of it. He does not appear anywhere else.
Around 6:07, some of the Teletubbies' corpses move slightly.
There is a very obvious inconsistency in terms of both Luigi and Toad's injuries. They are shown to have been wounded when the camera panned through the losers even though they were clearly shown to be killed by fire earlier.
At 11:14, all the injured contestants' battle damage suddenly vanishes.
Steve appears at 11:14 even though from 11:00 to 11:09, he was not present in the room.
Old Man Hobo does not appear from 11:00 onwards, even though his death was the same as Luigi and Toad's and they have been shown in the room as well.