This is generally considered one of the earliest uses a screenshot of the Red Alert 2 beta identifiable due to distinct pre release graphics tagged with the image macro I am in your base killing your d00ds It s also notable for the sentence being grammatically and syntactically correct until the very last word indicating its age even more it had yet to be exposed to internet slang corrupting it into the distinct i m in ur X Ying ur Z i m in ur base killin ur d00dz format However that image is from a blog and I know that s not a verifiable source but the facts can be obtained from the image Encyclopedia Dramatica also has an article on it search I am in your base killing your d00ds over on ED if you re that curious Not Starcraft not Counter Strike Red Alert 2 AFAIK