The stable would then refer to themselves as simply "The Nation". The Rock and The Nation then feuded with Triple H and D-Generation X, with the two stable leaders first meeting in the quarter-final of the 1998 King of the Ring tournament, which The Rock won. At King of the Ring, The Rock defeated Dan Severn in the semi-final match and lost to rival Ken Shamrock in the final. The Rock then resumed his feud with Triple H, as the two had a two out of three falls match at for the Intercontinental title, which The Rock retained in controversial fashion. This led to a ladder match at SummerSlam, where The Rock lost the title. The Rock saw a big uptick in fan support during this time, causing him to be booked in a feud with fellow Nation members Mark Henry and D'Lo Brown, turning babyface in the process. Henry defeated him at , after interference from Brown, effectively breaking up the stable. The Rock was then entered into the "Deadly Game" tournament for the vacant WWF Championship. The finals occurred at Survivor Series, where The Rock defeated Vince McMahon's associate, Mankind, to win his first WWF Championship. A "double turn" then occurred as The Rock turned heel again after allying with Vince and Shane McMahon as the crown jewel of their stable, The Corporation, after the McMahons betrayed Mankind. On December 13, 1998, at the pay-per-view named after him, , The Rock had a rematch with Mankind for the WWF Championship. Mankind appeared to win the match when The Rock passed out to the Mandible Claw submission move, but Vince McMahon ruled that since The Rock did not tap out, he retained his title. The Rock continued to feud with Mankind over the WWF Championship, which was traded back and forth between them. First, in the main event of the January 4, 1999 episode of "Raw Is War", Mankind defeated The Rock after interference from Stone Cold Steve Austin. Then at the Royal Rumble on January 24, The Rock regained the title in a brutal “I Quit” match, a type of match that only ends if one of the combatants says “I quit” on a microphone. Intended to show a vicious mean streak in The Rock's character, this match went horribly wrong as at the end of the match The Rock hit Mankind in the head with a steel chair 11 times instead of the scripted five, five shots already being a risky amount (most wrestling matches in the Attitude Era involving steel chairs had at most 2 or 3 shots to the head).