This article is from the 2006 series of SMBZ and is no longer canon.
Super Mario Bros. Z is based loosely on the events of Dragon Ball Z, making Mecha Sonic the Super Mario Bros. Z counterpart of Cell. Like Cell, Mecha Sonic has several different forms granting him increasing levels of power usually.
These are Mecha Sonic's primary forms and parallel Cell's transformations.
- Metal Sonic: Originally Mecha Sonic was known as Metal Sonic. Metal Sonic located and fused with the other three Sonic robots created by Dr. Eggman, transforming himself into Mecha Sonic.
- Semi-Super Mecha Sonic: By harnessing the power of at least four Chaos Emeralds, Mecha Sonic can enter this "semi-super" state. As the name suggests, this version of Mecha Sonic is vastly more powerful than his default form but not nearly as powerful as his super form. The only visual difference between Semi-Super and normal Mecha Sonic is that Semi-Super Mecha Sonic is golden while Mecha Sonic is blue. It seems that Mecha Sonic can maintain his Semi-Super form indefinitely, provided he has at least four Chaos Emeralds. It's shown that Semi-Super Mecha Sonic knows the Shun Goku Satsu (Raging Demon).
- Metallix: Mecha Sonic's super form is commonly referred to as "Metallix" or "Master Mecha Sonic". This is Mecha Sonic's strongest known form and requires all seven Chaos Emeralds. Although Metallix has not yet appeared in the actual series (aside from a silhouette appearance in Episode 5 during Sonic's nightmare), he has been shown in the anime-style intro to Super Mario Bros. Z. Alvin-Earthworm has also confirmed that Mecha Sonic will acquire all the Chaos Emeralds eventually, leaving little doubt that Metallix would have appeared in a future episode if it wasn't discontinued. It has been revealed, however, that Alvin-Earthworm intends to remodel his Metallix sprites, so the Metallix seen in the intro may not look the same as the one in the series proper. Metallix has, however, been seen in the flash collab Beat up Sandbag, in a scene created by Alvin-Earthworm. This form visually is an edit of the either Bass or Zero from the Mega Man series. Mecha Sonic holds un-paralleled sword skills, as well as the ability to control his sword remotely. It should be noted that the sprites themselves are made by Dave "Entrail" Burns. It should also be noted that Metallix is actually the name of the Metal Sonic(s) in the UK Sonic the Comic.
- 8-bit Mecha Sonic: Mecha Sonic is forced into this form while in the Minus World. This version of Mecha Sonic more closely resembles his Metal Sonic form. 8-bit Mecha Sonic lacks many of the abilities he can use outside of the Minus World, although this may be a result of the Minus World itself rather than a side effect of his 8-bit form. Despite this handicap, 8-bit Mecha Sonic is still strong enough to beat Sonic and Cape Mario (also in 8-bit forms). He also gains several curious abilities, such as the ability to stretch his arms to almost infinite length.
- Neo Metal Sonic: A form of Metal Sonic in Sonic Heroes. This form was rather the same size of Metal, only giving him an elf-like appearance plus a cape. In this form, he can shape-shift, as seen when he shape-shifted and impersonated Dr. Robotnik for the majority of Sonic Heroes.
- Metal Madness: A powered-up form of Neo Metal Sonic, he merely attacks Team Dark (Shadow, Rouge, and Omega), Team Rose (Amy Rose, Cream, and Big the Cat), and Team Chaotix (Espio the Chameleon, Charmy Bee, and Vector the Crocodile).
- Metal Overlord: The final form of Neo Metal Sonic. This form was a gargantuan monster, made by acquiring the data of Sonic and his friends combined with the power of Chaos and parts from Dr. Eggman's Egg Fleet. It possessed the strength to lift battleships, encapsulating crystals and powerful beam attacks. It was powered-down back to his regular form due to being weakened by Team Rose, Team Shadow, and Team Chaotix, and the timely appearance of Team Super Sonic (Super Sonic, Semi-Super Tails and Semi-Super Knuckles).
- Metal Sonic Kai: Enhanced by the power of the Dark Ring during the events of Knuckles Chaotix, Metal Sonic became a large, red, more cat-like version of itself with detached limbs and had the power to destroy an island. It was defeated by the Chaotix with the power of the Chaos Rings.
- Metal Sonic 0.3: In Sonic Rivals 2, Metal Sonic is upgraded by Eggman Nega into this form, he is yellow in colour, an outfit of this is also unlockable.