campaign start off adventure

[Christopher]

Rampaging monster in dowtown ,
Alien invasion,
Massive supervillain jailbreak,
just about anything that would draw multiple heroes to one spot, even if they've never met before.

In teh few campaigns I have started we had:
UNTIL collecting a superteam in a small city, because of a recent jailbreak/escape during transport.
Mole-Man borrowning up right in central park.

General Ideas:
Champions 6E also has a Plot generator that might be worth a look.
Make certain every hero has soemthing to do. Nohting more boring than Playing Master Mentalist and fighting Robots or multiple players having the same shtick.

[Kaze9999]

A villain bent on attacking them individually because of a mysterious vendetta based on something they have in common but do not realize they have in common.