If evil versions of us are gonna be used, I'm suggesting Union Jack one of the alternate Universe version of Jack Noir possessed by the big bad.

[hider=Union Jack][img]http://vignette3.wikia.nocookie.net/mspaintadventures/images/7/70/Jack_Noirglish.gif/revision/latest?cb=20130207003822[/img][/hider]
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As for worlds we can visit how about:
[list]
[*] The castle of Super Mario 64
[*] Hyrule
[*] The world of Avatar TLA/TLOK
[*] Middle Earth
[*] And of course I think Homestuck would be cool, but it would be best to stick to something everyone knows
[/list]