It really depends on how the fanfiction is written. If it follows the traditional power levels, Sonic with his super speed and ability to transform into Super Sonic could be very powerful. He has proven time and again to be able to take on strong foes.
Well, one possibility could be that Sonic and Eggman are forced to team up against Black Doom. Maybe Black Doom is threatening to destroy their world, and they realize that only by combining their strengths, Sonic's speed and Eggman's technology, can they stand a chance.
Tails would be the first one to come to Sonic's aid. His intelligence and flying ability would be very useful in finding Sonic and getting past Eggman's defenses.
A common theme is the battle between good and evil, with Sonic representing good and Eggman representing evil. They constantly fight over things like power, territory, or the Chaos Emeralds.
Well, obviously Sonic and Eggman are the main characters. Sonic is the speedy blue hero, always ready to save the day. Eggman, on the other hand, is the brilliant but often - misguided inventor. In fanfiction, their relationship can be re - imagined in many ways.
A really cool Sonic and Eggman fanfiction could be set in an alternate universe. In this universe, Sonic is not the hero he is in the main canon. Instead, he's more of an anti - hero, and Eggman is the one trying to save the world from Sonic's reckless behavior. It flips the traditional roles and makes for a very engaging read.
In this kind of fanfiction, Sonic might be locked in one of Eggman's elaborate traps. Eggman could be planning to use Sonic's speed for his own evil experiments or to finally defeat him once and for all. Sonic would surely try to escape using his wits and speed.
A common theme is the power struggle. Eggman is always trying to gain power over Sonic's world, and Sonic is there to stop him. Another theme is redemption. Sometimes fanfics explore the idea of Eggman having a change of heart.
Eggman's death in the Sonic comic was a game-changer. It could potentially lead to new villains emerging or heroes having to step up in a big way. It was a bold move by the creators to keep the story fresh and exciting.