Following the feud with Cena, he would move onto some new talent like Roman Reigns and then Seth Rollins. Brock would begin the feud that still hasn't ended on the Road to WrestleMania 31 against Roman Reigns. It was at Battleground 2015 when Seth would become the first person to loose to Brock not by pin fall and Brock would move to a feud with the returning Undertaker. Since his feud with Undertaker his run has really lost it's way somewhat and even though I did enjoy his feud with Goldberg I feel like Brock is nearing the right time to retire.
At this point, I think that the aura of Lesnar is fading which isn't surprising since he has been with the WWE for the last five years. The WWE is running out of big and believable matches for Lesnar to participate in. With the rumors starting up that fight between Jon Jones and Brock Lesnar it is brining up the question of how long will Brock remain with WWE or if he will rejoin UFC.