Super Mario Bros. Z

Super Mario Bros. Z is another fan made project based around Super Mario and Sonic the Hedgehog created by Mark Haynes or his screen name, Alvin-Earthworm. The story sees the two worlds intertwine in a race to save the Chaos Emeralds from Metal Sonic combined other Sonic-based androids. It has a huge following. The series was discontinued for a time. but returned in 2015 with a reboot. No episodes have been posted since.

2006 Series
In the original series, Mario, Luigi, Wario and Waluigi were competing in a grand prix when Bowser set off a bomb, postponing the race. Bowser declared a battle to the death against Mario, which Mario accepts. The fight starts off in Mario's favor, but when Bowser uses a Metal Mushroom, the fight nearly ends with Bowser as the winner. Just before he can finish Mario off, a large capsule falls from the sky, landing on Bowser and making him lose his powerup. Luigi gives Mario a Cape Feather, which Mario uses to fight Bowser. Before he can defeat him, Kamek intervenes by threatening to turn Princess Peach into a Goomba. Mario surrenders, but Sonic the Hedgehog and Shadow stop Kamek, letting Mario defeat Bowser. They then ask for Mario, which they reply that they're in the right place. Sonic and Shadow introduce themselves and inadvertently warn Mario and Luigi about the threat of the Chaos Emeralds. Asking for help, Mario comes to their aid, as well as Luigi and Yoshi. Luigi and Yoshi find a Chaos Emerald hanging by a cliff edge, but when Yoshi goes to grab it the cliff breaks, sending him off the cliff with the emerald in tow. Once reaching the bottom, Yoshi meets Mecha Sonic who asks politely for the emerald which Yoshi denies him the emerald by swallowing, which leads into a fight. Yoshi tries his best, but is defeated by Mecha Sonic, and the emerald is stolen from him. Mecha Sonic escapes before Mario and Sonic can get there, leaving Yoshi there injured. After they save Yoshi's life Sonic tells Mario and Sonic the reason why they're in the Mushroom Kingdom. Metal Sonic was a creation by Doctor Eggman which was meant to be Sonic's equal, but to no avail. In anger and revenge, Metal Sonic merged with several other Sonic androids meant to replace him. After Eggman finds out, he threatens to shut Metal Sonic down, which causes the newly formed Mecha Sonic to rebel against his creator and bring down the Death Egg into Mobius. The explosion causes the whole world to be covered in drak smoke, which Mecha Sonic uses to his advantage to collect the Chaos Emeralds and destroy Sonic and his friends. After killing his friends aside from Shadow, who he cannot best without emeralds, Sonic holds the last emerald, which Mecha Sonic fights him for. Sonic is defeated and Mecha Sonic begins his transformation. Shadow intervenes, teleporting the emeralds to the Mushroom Kingdom, where Mecha Sonic follows them. Sonic and Shadow return to the Death Egg to find a teleporter, which miraculously works. They followed Mecha Sonic and the Emeralds to the kingdom where their plan was to find them first before Mecha Sonic could destroy both worlds. With that impending doom, Mario and Luigi agree to work with Sonic and Shadow to find them before Mecha Sonic does.

-This page is in the works-

Trivia

 * According to CaptainKodachrome, Super Mario Bros. Z was a major contributor and inspiration for The Lost Brother and it's fighting scenes.