Conversation so far:
What is the corporation?
The Rock allied with Vince and Shane McMahon as the crown jewel of their stable, The Corporation.
What can you tell me about the corporation?
beginning a feud with Triple H, The Undertaker and The Corporate Ministry that saw The Rock defeating Triple H.
what did they do in the corporation?
The Rock, who then lost the title rematch at Backlash: In Your House and was thus betrayed by Shane McMahon.
When did he join the corporation?
On December 13, 1998.
Are there any other interesting aspects about this article?
The Rock's entertaining promos and ensuing popularity led to a face turn, in which he called himself "The People's Champion".
did he have any other names during that time?
CANNOTANSWER.
Who did he fight against?
The Rock defeated McMahon's associate, Mankind, in the finals of the "Deadly Game" tournament for the vacant WWF Championship.

Question: who else did he defeat?
Self-contained rewrite: who else did The Rock defeat aside from Mankind?