yes u have to beat all the story modes get keys in the stages clear the stages with out getting hit and chase one chaos emerald each key
get 7 chaos emeralds
He copied Sonic's abilities and copied Chocola's and Froggy's Chaos DNA.
finish all 4 stories and get all 7 chaos emeralds to unlock the last story
You have to Finish the game with all the team. Then a new stage will appear (on team selection screen i suppose). Not only that, but you must get all 7 Chaos Emeralds, (It doesn't matter which team you get any of them with,) and then you can battle Metal Sonic.
Once you get the 7 choas emeralds this level will be unlocked to get the choas emeralds get the hidden key and keep it without getting hit then get the choas emerald on the final level before it exits the end of the stage
What you have to do is finish the game get all the chaos emaralds [on the bonus stages] complete th game with them all or it will not work. Then when you jump whilse in the air press jump again and then you should transform into onic higher form "supersonic"
You have to beat egg emperor with all the teams and get all the chaos emeralds to get to metal sonic.
On the screen where it has the teams; go to Chaotix and go right once more; it has a siluet of Neo Metal Sonic. You need all of the 7 Chaos Emeralds collected to unlock this story.
u can do it on both
Easy You need to collect all 7 chaos emeralds From each special stage (sonic 1-4) Mostly the other games hand then to you But in sonic generations you have to beat the rivals (metal sonic shadow silver) to get 3 of the chaos emeralds And you have the beat each time periods (classic dreamcast and modern) to get another 3. the last one i belive is handed to you.
Metal Overlord, Metal Sonic after having absorbed the energy of Chaos, Shadow and some other people.Although personally, That last answer did give me the giggles.
If you have beaten all 4 stories, you unlock a "Last Story" where you fight the real final boss.(Spoiler alert: it's Metal Sonic)