A fork of Rural Dictionary
Most likley derived from the term OMG by those who chose being offensive to the extremley religous more important than saving themselves the painstaking work of typing 2 extra letters or keeping the versatility of the term OMG (by narrowing it down to simply "Oh my god" instead of "Oh my gosh", "Oh my goodness", etc. )
"OMGod u suk at dis game n00b!"