Sonic The Hedgehog:Catalyst also known as STH:C is a 2012 CGI-Animated Sonic Film,it was heavily promoted by sony who was releasing the film at the time. It acts as a prequel to Sonic 2006 and so takes place in an alternate timeline.
In the year 2018,In Sonics world Many of the worlds top scientists discover mysterious crystal near te earths core that are later found out to be time crystals letting the user of them control time itself and when they are all fused together then it becomes a giga time crystal letting the user time travel,control space and even distort reality but to make sure it doesn't fall into the wrong hands,G.U.N locked it down in a heavily protected base underneath Kingdom Valley.
Twenty years later,Mephiles The Dark discovers the base after allying with Dr.Eggman with Metal Sonic and soon Mephiles gathers 6 of the 8 Time Crystals for Dr.Eggman so he could upgrade metal sonic and make mephiles even more powerful than he could have dreamed. Soon shadow learns about this after being sent on a mission to learn about Dr Eggmans Plan and soon informs sonic and silver learn about this. Soon,Mephiles kidnaps tails and knuckles to use them to find the two last time crystals at two lands,Chaos Tundra and Iron Ocean, a city above a fair mass of ocean held by powerful metal beams. After being lied by tails,mephiles leave him for dead in a cavern in the tundra and drowns knuckles unconiscous at the bottom of the ocean but mentally aware of his situation. Soon Sonic,Silver and Shadow arrive via G.U.N Transport at Chaos Tundra to rescue tails and afterwards manage to convice him to fix the tornado but then tails reveals he has retrieved the seventh time crystal and convinces sonic to keep it and keep it as a secret away from mephiles then hands him a fake time crystal to fool mephiles. Soon they arrive at iron ocean and to the dismay of sonic, shadow and silver go out into the depths to rescue knuckles for sonic because of his chronic fear of water,soon knuckles returns and gives shadow the eighth time crystal.
Mephiles learns of the heroes antics and later plans his revenge on the three hedgehogs. Our heroes return to a large beatiful field outside Soleanna and so shadow sees mephiles and chases him through the market before mephiles escapes to his secret underground base which used to be the base that housed the heavily protected time crystals letting mephiles execute his master plan which is once he gets all the time crystals meaning he could change time so he rules the world. Afterwards Mephiles escapes in his large airship which sonic,shadow,tails and silver latch onto and soon after heading into the inside of the airship where Mephiles begins his final transformation into time breaker mephiles so to counteract this devious transformation the three hedgehogs and tails get out the chaos emeralds and become their super forms. Soon they defeat mephiles but to the Cost of an heavily damaged tails who ends up in a coma and silver possibly dying so sonic,shadow and a heavily damaged and a comatose tails return to their Home in Soleanna.
After Sonic:Catalyst made tons of money at the box office,two sequels were released one of which was non-canon,Sonic The Hedgehog:Shattered Memories A cartoon network film released in 2014 that focuses on shadow and silver trying to regain his memories and Sonic The Hedgehog:Origins an Internet Cel shaded animated mini-series that focuses more on the origins of the villains like Mephiles and even Metal Shadow and Metal Silver.
Roger Craig Smith as Sonic The Hedgehog
Jason Griffith as Shadow The Hedgehog
Pete Cappella as Silver The Hedgehog
Tara Strong as Tails The Fox
Marlon Saunders as Knuckles The Echinda
John DiMaggio as Mephiles The Dark/Mephiles Time Breaker Form
Fred Tatioscore as G.U.N Soldier 1/Other Humans and Characters
Many Critics heavily critiqued the film for it's nonsensical and non consistent plot and storyline but the fanbase liked it slightly despite it having connections to 06. Rotten Tomatos and IMDB gave the film a 9 causing a controversy where fans believed that sega had been bribing these websites with free games and Iphones,ons of the most well-known critics of the film,Doug walker,described it as a drugged up and failed attempt to make a good version of 06's plot.