SMG4: Mario The Supreme Leader is the eighteenth episode of Season 10 and the five hundred and seventy-second overall to be uploaded by SMG4.
This episode was aired on May 16th, 2020.
All hail Mario, our lord and savior. 👑
The video begins with Mario narrating how he suddenly became the monarch of the Mushroom Kingdom. 5 minutes ago, Princess Peach left Toadsworth in charge of the Kingdom with her crown signifying that people know who's in charge. Mario later came to the castle wanting to show Toadsworth his new pet rock which later opens a portal sucking Toadsworth in it. Seeing the crown he dropped off, he took it and wore it, proclaiming himself to be king, as Mario the first. As one of Toads servant rushes to find the princess, he spots Mario with the crown and drags him along to the throne room to decide if he were to punish Bob for ransacking the castle. Despite Bob appealing to being friends with Mario, Mario, despite his inexperience, rightfully decided that Bob's spine be broken, which made Chargin' Chuck break Bob's spine, causing Bob to shrink, and complain that his spine had been broken yet again.
Next, a Toad servant complained about polluted water in the lake, which was revealed to be caused by Donkey Kong defecating in the lake. Mario has him caught and executed via a guillotine. A montage is then shown of Mario's efficiency as a king, as he is able to solve many problems and crises that show up from the Toad servants and governors, including:
Everything seems to be fine, as the Toads now salute him, which then leads to Mario being more power-hungry than ever before. From then onwards, he would now use his personal bodyguards to shoot his problems away.
In the first incident, bandits are invading the Mushroom Kingdom, involving the Goombas attacking the civilians with baseball bats, and with Monty Mole and a Boo demanding another Toad at his stand for food, while wielding swords. King Mario suggests to destroy all the bandits, as a way to get rid of them. His Toad servants agree without hesitation, shooting the bandits out of the kingdom, then cheering because they won.
In the next incident, King Mario goes onto the roof of the castle to find Bowser dressed in a Princess outfit, wanting to marry King Mario so he can become the queen of the Mushroom Kingdom. King Mario immediately says to destroy him, with his Toad Servants arriving behind him, but questioning why he wants them to kill him. Mario then forces them to do it, and so they follow his orders, shooting Bowser off of the roof.
In the final incident, the villagers went to the castle to protest about the rising taxes. King Mario then suggested the very same thing, to destroy them all to be able to get rid of the demanding protesters. The toads look at each other and question King Mario, so he instead yells at them twice to do as he says. Then, the Royal Guards came out of the front of the castle against their will, and shot the protesters away. Seeing as King Mario rising with too much power, two of the Toads agree that he has gone mad with power, but they cannot question him because he is the king.
A few weeks later, Mario, now the Supreme Leader, had converted the monarchy from a constitutional one to that of absolute monarchy, renaming the Mushroom Kingdom to Mario Land. He treats the citizens and his friends poorly, threatening the citizens with death should they not obey him, forcing Meggy, Axol, Shroomy, Tari and Saiko to work for him, trapping Bob in a cage (which was actually unlocked), refusing to give his brother Luigi any food (causing Luigi to starve and become dangerously skinny), and banning memes, causing SMG4, who loves memes, to become an old man in response. He made his entrance in an impoverished part of Obey Square on a throne on a coffin, carried by some Royal Toad Guards wearing black, as Shroomy and Axol, now members of the Royal Guard Marching Band, announced his arrival playing Astronomia. Fed up with the continuous poverty that everyone had to go through and a new law (forcing everyone to play on his Minecraft server every day) that had gone too far, Meggy and her friends stood up against the dictatorial King, who became quickly agitated with this defiance, and sent the Royal Guards and the RMKP Toads after them, trying their best to quell the rebellion.
As the gang managed to defend themselves from the authorities, Mario became angrier and sent civilians to take them down (promising anyone who was successful ownership of Bob-omb Battlefield, much to King Bob-omb's ire). The gang then prepared themselves against this second wave, before being stopped by Peach who returned from her vacation and was angered at what was happening. She took back her crown from Mario and slapped him in anger for letting his power go into his head, restoring the monarchy back to a constitutional one and making the civilians happy again, who carried her back to the castle. Mario, now no longer power-hungry, asked for his friends, who were frozen in shock, to come over to his house for some spaghetti, making all of them collapse to the ground, ending the episode.