Mario is one of the main protagonists in Super Smash Bros. Crossover. Unlike the games, Mario talks a lot more. Mario is still the same hero he always is. Mario fights by using Power-Ups and his fists. In Season 6, Mario battles against the Axem Rangers X (all 6) and wins. In Season 7, he takes one of the Chaos Bakugan and heads to the Mushroom Kingdom to battle Cell in Naruto's place. While Mario is saddened about what Cell's fate will be if he loses, Mario doesn't give up and wins against Cell. Mario is infected during the events of Season 18, and is cured during Season 19. In Season 23, Mario, Luigi, and their younger selves hear something while going through White Space, and meet up with their retro selves. The 3 Marios and Luigis join forces at this point, and manage to defeat Modern and Classic Metal Sonic. Mario, Baby Mario, and Retro Mario then let the Luigis handle Retro Bowser while the Marios pursue Classic Dr. Eggman. Using teamwork, Mario, Retro Mario, and Baby Mario are able to defeat Classic Dr. Eggman's Death Egg Robot. In Season 24, Mario is seen training with Luigi when he notices the eruption coming from Volcano Island, and later helps the Heroes of Legend and, unknown to Mario, the League of Villains escape the wrath of Fleetway Super Sonic. In Season 25, Mario battles against Anubias and despite being overwhelmed a few times due to interruptions, Mario is able to defeat Anubias, making him the first character to defeat a Hero of Legend that isn't a member of the group. Later, Mario finds himself in a strange situation when the Heroes of Legend purge the evil from their souls, only for it to manifest as an evil version of Bowser. Despite this, Mario is able to defeat this clone of Bowser with little difficulty. At the end of Season 25, Mario becomes a Hero of Legend after Rosalina provides the Heroes of Legend, Luigi, Shadow the Hedgehog, Yoshi, Silver the Hedgehog, Ben Tennyson, and Mario himself with a new version of the Smash Core. In Season 27, Mario would battle against Metal Mario, but the fight was left with no outcome as Metal Mario would launch a Smoke Ball to cause a diversion while he retreated with the other villains. In Season 28, Mario fought alongside Yoshi against Marth, but is brutally defeated by his corrupted former friend, forcing Yoshi to get Mario out of Norfair to ensure his survival. In Season 34, Mario battles against Link to determine if he can be trusted again, but ultimately puts all his strength into one final punch to defeat Link when it becomes apparent that Link intends to kill Mario. Having used up all his energy, Mario falls off the Battlefield, and it is presumed that he died as Mario's spirit appears to encourage the Heroes of Legend to continue fighting. However, it is later revealed that Mario miraculously survived his fight with Link, as he arrives in the Twilight Realm with Thor to help the Heroes of Legend and the Creator's Triune defeat Midna. In Season 35, it is revealed that Mario was the one who sent the broadcast that motivated the Heroes of Legend to continue fighting Midna and has retained his memories of the First Cycle like Bowser and Sonic. In Season 36, Mario sacrifices himself to prevent Sasuke from killing Bowser so that Peach won't become consumed with despair if Bowser was killed. Mario is later revived after Sonic.exe is defeated, and is now determined to save Peach and Bowser from their path of revenge.
Baby Mario is Mario's toddler counterpart. While Baby Mario appeared in the past to compete in races, he plays a major role during the Time Eater Arc where he, along with younger versions of the other heroes, get thrusted into a strange world that was created when Time Eater damaged the timeline. He then joins up with his older self to reverse the damage. Baby Mario later teams up with Mario again during the Fight to the Finish 2 Arc, and meets his retro counterpart during this time.
Retro Mario is Mario as he appeared in the first Super Mario Bros. Retro Mario and Retro Luigi are first seen exploring the White Space when they enter a hallway with a glass wall and see their toddler and future selves. However, they all hear Dr. Eggman's voice and the Retro Mario Bros. go after Classic Dr. Eggman, who has Classic and Modern Metal Sonic deal with them. However, the Retro Mario Bros. gain assistance from their past and future counterparts. After beating Metal Sonic, Retro Mario, Mario, and Baby Mario pursue Classic Dr. Eggman while the Luigis handle Retro Bowser.
Unlike Mario and Baby Mario (who really speaks gibberish), Retro Mario doesn't talk at all, though he makes the coin collecting sound effect when he is curious, and shows his pure heart through his actions.
Mario has an excellent battle record, as nearly every one of his fights have ended in victory. Season 26 marks the first time Mario has ever been defeated, as he and the other Heroes of Legend were defeated by Lena Isis and Mariyo.
Axem Rangers X
Metal Sonic (Modern and Classic)
Win (Tag with Baby Mario, Retro Mario, Luigi, Baby Luigi, and Retro Luigi)
Mario, Luigi, Sonic the Hedgehog, and Dr. Eggman are the only characters that work with 2 of their younger counterparts.
Mario is incredibly powerful, as he has won most of his battles and was able to defeat Cell, who was very powerful, and all 6 of the Axem Rangers X at once. Another sign of his strength was shown when he got all the Heroes of Legend and the League of Villains off of Volcano Island with ease despite the amount of people he was carrying.
Mario was the strongest non-Hero of Legend in the series, since he was able to defeat Anubias all by himself, though he did struggle a bit. Like with Pichu, this was probably a foreshadowing of Mario becoming a member of the group.