probably a best powerleveling tactic : City of Heroes - Submissions

ok I do this all the time with my friends. First of all, you need to be someone with aoe attacks like a fire/fire tanker for instance. What I do is make sure my friend is at a high enough level to go into perez park, I need to be 6-4 levels above him. make him follow you wherever you go but keep a distance so he/she doesn't get killed. All you do is get as many mobs on you as you can, and aoe the heck out of them. because I am a fire/fire tanker, I put Blazing Aura on, Fire Shield, have Combustion ready, and Consume for when your low on endurance. I leveled my friend up quite a few times with this really fast. Oh yeah you have to slot all your aoe attacks with damage enhancements. That is how I powerlevel my friends and I hope it will get me a premium membership. Thank You.

Can only pull 16 things tops. the AOE fire attack that fire tankers get now has a very long cooldown, so its pretty much useless.