Very few people have been as dominate in their WWE careers as Brock has been from his first stint with the company to his more recent stint with them now. Brock has been a breath of fresh for a very weak roster in the WWE. After Brock's time in the UFC ended and he got his butt whip by then UFC Champion Cain Velasquez, the rumors began to fly he was in talks to return to the WWE. On April 2nd 2012 the rumors were proven true as Brock Lesnar returned to the WWE for the first time in 8 years by attacking John Cena and jumping right into his first feud. Now a year later Brock has also feuded with Triple H and had a short feud with CM Punk over the summer. Now Brock is the rumored opponent for Undertaker at Wrestlemania this year which will be a big match. But after Undertaker I don't know how many people Brock has left to face that could produce big money like his other matches have.
A little list of achievements thus far in Brock's career:
3 Time WWE Champion,
2002 King of The Ring Champion,
2003 Royal Rumble Winner,
1 Time IWGP Heavyweight Champion
Below a video of what I think is Brock's best match: