The Super Mario Bros. franchise usually tends to be bright and cheery. However, that doesn't mean it's afraid to get grittier at times.
- The Mario RPGs as a whole tend to be darker and more dramatic than most of the main series Mario games;
- Paper Mario
- Paper Mario: The Thousand-Year Door is noticeably darker than Paper Mario 64. Set in the crime ridden town of Rogueport, the first sign of many that this game will be darker than the last is probably the gallows in Rogueport's town square. This is also a game in which Mario does jobs for the Mafia. Many of the areas in the game — notably Twilight Town and its surrounding areas, Riverside Station, the Pit of 100 Trials, and the final dungeon itself — have a creepy atmosphere by any standard, let alone those of the famously family-friendly Mario franchise. One of the party members is depicted has having suffering fairly realistic abuse under her Big Sister Bully, which includes transphobic insults in certain translations. Finally the main villain wants to inflict Darkness across the whole world and it's not Played for Laughs. Nonetheless, the whole thing is fairly cheery and innocuous, at least until the final act.
- Super Paper Mario is even darker, what with Mario and company saving the multiverse from an Omnicidal Maniac who’s also a Tragic Villain with a really heart wrenching backstory and his dysfunctional flunkies. Worst of the lot is Mimi, whose transformation into her true form is accompanied by sickening cracking sounds while her neck spins around, and Dimentio, who is basically the in-universe version of The Joker. In Chapter 6, an entire dimension even gets wiped from existence before Mario and friends can save it, they’re forced to trek through the empty remains while eerie music plays that sound more befitting of a horror game, and Dimentio teleports Luigi, Mario, Peach and Bowser to the afterlife. The level immediately after is a thinly-veiled version of Hell. The game is arguably the darkest entry not just in the Paper Mario games, but also the entire Mario franchise.
- While it's not as dark as Super, Paper Mario: The Origami King is still far from sunshine and roses, as the game begins with Peach already Brainwashed and Crazy by Olly, there are frequent cases of Nightmare Fuel and Body Horror, and the situation is so dire that Mario and Bowser have to team up to stop it. Olly’s henchmen, the Legion of Stationary, while somewhat goofy, use their powers to terrorize the paper cast whenever possible (including Hole Punch, who bites the faces off characters, and Scissors, which cuts them to pieces). On top of that, the villain plans to make a wish that will essentially erase all Toads from existence, three named characters (Olly, his sister Olivia (the game's Exposition Fairy), and adorable Guest-Star Party Member Bobby the Bob-Omb) are Killed Off for Real, and the game ultimately ends on a Bittersweet Ending after Olivia sacrifices herself to reverse her brother's damage even though it'll make it so she never existed as a result.
- Mario & Luigi
- Before Super Paper Mario, the title of darkest Mario game went to Mario & Luigi: Partners in Time. It is based around an alien invasion of the past Mushroom Kingdom and has places like Toad Town and Princess Peach's Castle turned to ruins by the Shroobs with some rather creepy things as background detail and music. It actually introduces a Christmas-themed village solely to destroy before Mario and Luigi even get there. Toad Town is just pieces of rubble tossed around; compare it to Toad Town of Bowser's Inside Story. Even Peach's Castle from the latter isn't as devastated and dangerous as Shroob Castle.
- Mario & Luigi: Dream Team starts off lighthearted, then you get to Dream's Deep (which is a surreal area where you read Luigi's thoughts) and meet Antasma, who teams up with Bowser, who seems like his regular comic relief self and they soon steal the dream stone together. However, most of the darkness is in the second half, Antasma uses the dreambeats to induce sleep and steal their dream energy, Bowser uses his new castle to destroy the nearby barrier islands, the island is in a panic, and it just gets worse from there. And then there's the ending part of the game where Bowser betrays Antasma, anticipating that he was planning on doing what earlier villains did, then later Bowser eats the dream stone and becomes a rainbow-coloured Eldritch Abomination with plans to Take Over the World.
- Despite Mario & Luigi: Paper Jam being an Affectionate Parody with Better than a Bare Bulb humour, it still features Bowser (both of him) at his darkest. The Bowsers kidnap Toads and make them into their slaves, nearly kills everyone when they destroy Peach's Castle with their latest weapon and then try to send the Bros. into the Paper world and then destroy it and everyone in it. Remember, this is in a Mario game.
- Paper Mario
- Mario Strikers did this among the sports branch of Mario games, albeit in a rather tongue-in-cheek, over-the-top way. The sequel, Mario Strikers Charged invokes this in universe as the games have gotten so violent that metal body armor is now mandatory for all players.
- Not that the main series Platformers can't get darker from time to time, New Super Mario Bros. actually deconstructs the iconic "Bowser on the bridge" scene from SMB1. This time, when he falls into the lava he gets his flesh completely melted off, only for him to come back to life later as Dry Bowser, and then revived completely thanks to Bowser Jr.
- In Super Mario Galaxy 1 and 2, Bowser tries to take over outer space. Notably, the first Galaxy game also features gruesome death animations for Mario, a not-so-happy backstory about Rosalina, and a surreal ending.
- Luigi's Mansion: Dark Moon starts out as following the first game's lead in being a parody of the survival horror genre. At that point, however, it's shown that King Boo went from a Well-Intentioned Extremist to an unfettered sociopath. This carries over into Luigi's Mansion 3.
