Mario VS Sonic: PRANK BATTLE is the thirdy-second episode of Season 7 and the three hundred and ninth overall to be uploaded by SMG4.
This episode was aired on August 12, 2017.
When Frankie was climbing up the slide, Mario moved the slide to a building top, causing Frankie to slide off of the roof and most likely to his death. Sonic said that prank was lame so he pranks Toadette. When Toadette was on the spinner, Sonic uses his super-speed to spin the spinner very fast causing it to fly into space, taking her with it. Sonic then asks: "How about that", but Mario still thinks he is better than the Blue Blur, so they decide to have a prank war.
Goal: Creep The Most People
Mario hid under a bench and creeps out both a Goomba and a Koopa. He also creeps out a Shy Guy by singing a ridiculous and weird song as well as Wario and FightingMario54321. Then, Sonic reads a Sonic fanfic and everyone runs away, much to Mario's anger, making Sonic the winner.
Goal: Scare Luigi The Most
Sonic easily scares Luigi by using a creepy Mario mask, but Mario is having problems, as Luigi is not scared by Mario's attempt: using a Boo puppet. After many failed attempts at trying to scare Luigi, Mario tells Bowser to lick his balls while he was walking on the street just after bypassing Luigi, to make it look like Luigi said that. Angry, Bowser attacks and burns Luigi, while Mario celebrates his victory.
Goal: Get Toad In Trouble
Sonic goes up to Toad asking him to take care of his stuff while he's shopping, consisting of a shovel, a bat, a knife, a shotgun, a dead corpse, and a ballistic missile. 7 hours later, a cop comes in with Toad (holding the shotgun and bat) greeting him.
Afterward, Toad and Toadette are dining at a restaurant, much to Toad's disgust. Toad then goes to the bathroom, and Mario (holding both a waifu pillow and a Toad decoy) fools Toadette into thinking Toad dumped her, much to her fury (and disgusting SMG4 who decides to go the other way). As a result, when Toad returned, Toadette angrily blasted him away from the restaurant with a tank, causing Mario to win this round.
Goal: Do The Best Elevator Prank
Inside a building, an elevator comes in with many people with Mario coming out. A man then goes to the elevator and Mario walks away, only to tell him that he dropped something. The chubby plumber then hands the man a grenade who thanked him for returning his dropped item. However, upon closer inspection, he freaked out upon seeing the grenade, causing all the other passengers to freak out too. As the elevator doors close, Mario claimed it was just a fake grenade, just to hear an explosion from the elevator. Fearing the repercussions, Mario silently walked away.
Meanwhile, Sonic tries to give Waluigi the ride of his life by using his speed to pull the elevator. Unfortunately for the Blue Blur, his supersonic speed is too much, and he ends up sending Waluigi into space where he found Toadette still stuck to the spinner from earlier.
Goal: Prank Someone With A Novelty Toy
Mario goes to the novelty store and buys a hand buzzer, hoping to electrocute anyone who touches his hand. He then attempts to have a Shy Guy touch his hand, only for it to run away at the sight of him. Mario then notices SMG4 hanging for dear life at a parking lot building and attempts to use his hand buzzer to fool SMG4 into thinking he's going to save him. However, the YouTuber notices the trick, instead decides to fall from the parking lot building, much to Mario's annoyance.
Mario needs at least one person to be shocked, and tricks Heavy Weapons Guy into high fiving him after he does a slam dunk. Unfortunately, he accidentally brings the buzzer to full power, blowing away Heavy's hand, and angry he brutally beats up the red-capped plumber.
THE DEATH BATTLE!
Sonic meets with the bruised Mario, who quickly gets mad at him for entering his "Pranking turf". The Blue Blur then convinces him to relax with him, only for Mario to fall for the whoopee cushion trick. Already on his limits, Mario angrily tackles Sonic and uses his hand buzzer to electrocute him before he kicks him and throws a fake spaghetti to punch the plumber in the face. Sonic then uses his spin dash, only for Mario to throw thousands of other hand buzzers into the ground causing the hedgehog to get severely electrocuted. Mario simply laughs until he accidentally jumps on a spring, sending him flying into a dumpster filled with mouse traps that Sonic had set up. As the red-capped plumber screams in pain, Sonic starts laughing, only to realize that the injured Mario is right behind him and about to shoot him.
Sonic begs for mercy, only to realize it's the fake gun trap. Traumatized though, he punches Mario in the face, and annoyed, the two decide to viciously prank each other until they can't take it. After numerous pranks which (more often than not) get them injured and hurt, the two put fireworks into each other's karts. After seeing what they're doing, they quickly set the fireworks and run to their karts, only to send themselves into space. Sonic quickly gets angry, as they can't do pranks in space, but Mario doesn't care and they start tackling each other until they notice Waluigi's new taco stand. Deciding to stop, Mario and Sonic apologize to each other and go off to eat tacos, while Toadette (who's somehow still in the spinner) ends the video by saying "Somebody kill me!"