In most RP's, godmoding is against the rules and will get anyone doing it kicked out.
Other Guy: *incinerates corpse*
*ashes blow away in wind*
Fucktard: I use my powers of regeneration
to completely totally and utterly heal my body then I blow you up witha nuculear blast powerful enough to destroy Australia!
Me: Hey! You never said anything about those powers you god-modding Fucktard!