>>136226838Sonic would hate forced immortality at the expense/rejection of others and losing all his friends in the process. What Merlina was doing was less "granting everyone immortality with their explicit consent and understanding" and was more a hostile takeover and having the forces of the Underworld slaughter everything in their path in an attempt to forcibly prolong the Arthurian tale.
Sonic would probably be fine if it was just natural immortality or the chaos emeralds granting him that power from extensive exposure. I think the worst it would cause is resulting in him succumbing to ennui and perpetual boredom once Eggman dies. And naturally, like everything - depends on the continuity. Fleetway wouldn't care if he was made immortal so long as he could protect Mobius, Archie MIGHT react a bit negatively, IDW would have a panic attack, Movie would only want it if his family and town got it too, etc.