#1 Hulk Hogan joins the nWo
I'm sorry, WWE, but the best swerve in professional wrestling history doesn't belong to you, but to your arch rivals from the 1990's Monday Night Wars, WCW. And, what a swerve it was. It nearly caused the collapse of the WWE, after all.
With Scott Hall and Kevin Nash jumping ship from WWE to WCW, they debuted as The Outsiders, attacking everyone and saying they were going to take over. And, that's exactly what they did for weeks while teasing the debut of a third member.
When Hulk Hogan appeared at Bash at the Beach 1996, everyone thought he was there to help his old ally, The Macho Man, Randy Savage. Instead, he stunned the entire planet into disbelief by revealing himself as the third man.
Turning heel, he dropped his patented Leg Drop on Savage and allied with The Outsiders to form the New World Order. The nWo would go on to become one of the greatest factions in professional wrestling history and it was all down to this one epic swerve.