:: comic canon

• Sonic::Epilogue is a SATAM older AU. Tails is 14 in it, for example. 
• Robotnik is dead, and Snivley took over the empire. 

- Specifically regarding Sonic

• Sonic was captured and injected with some sort of red substance. The injection hurt a shit ton, and a few hours after, it took over the Sonic we know, and replaced him with…what you see here. 
• The finale movie implies that when Sonic was injected, his memories were wiped as soon as it took over. The only thing Sonic remembers, thanks to Snivley, is his name. 
• The injection changed Sonic’s personality a shit ton. From snarky, big hearted, attitude-filled Sonic, comes a ruthless, jerkass loner Sonic. The only thing that kind of stayed is the attitude; and even then, it’s to make fun of who used to be his friends. 
• The injection was never truly explained, but according to the finale movie, the only way to free Sonic completely…is death. 

If you would like to know more, the only issue and finale movie are to the sidebar.