#1 The Undertaker
While many superstars have impacted the image of SmackDown, The Undertaker literally owned the brand when he was a part of it.
He moved to SmackDown in 2002, and remained there for the time he was in active competition. Throughout that time, he was the most dominant and feared wrestler in the SmackDown roster, and also the main face of the blue brand.
On SmackDown he won three World Heavyweight Championships and was a constant pay-per-view headliner for the brand. Not only that, but he also helped establish and put over a number of future WWE Champions, providing great service to the company.
The Phenom is by far the greatest wrestler to have been on SmackDown, and that’s one of the reasons he remains WWE’s longest-tenured superstar to date.