#15 Brock Lesnar vs. Randy Orton - Summerslam 2016

The most recent main event on the list finds itself roughly in the mid-way position. The match certainly left an impression - most notably on The Viper's head, and was a pretty standard day at the office for The Beast.
This was not long after the brand split following the WWE Draft. Orton was representing Smackdown and Lesnar was championing RAW. The build up had some pretty decent scenes with both men invading each other's show and Orton delivering his 'no enhancements necessary' line that caught everyone's attention.
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The match won't be remembered for very long, but at the time it was definitely a passable enough main event.
#14 Brock Lesnar vs. Triple H - Summerslam 2012

The feud between Triple H and Brock Lesnar from 2012 felt a little unnecessary at the time. This was in the midst of CM Punk's lengthy title reign and John Cena's feud with the Big Show.
Triple H and Brock were basically put together because neither had anything else to do.
The fact that this main evented ahead of Punk's bout against Cena and Big Show annoyed quite a few people at the time, but the match was strong and gave Brock a signature victory against a legend on his way to the top of the mountain.
Both men have had better matches, but it still makes the top half of the main event list overall.
#13 The Undertaker vs. Brock Lesnar - Summerslam 2015

Out of all the matches on this list, few had a better build up than Taker vs. Lesnar at Summerslam 2015. After his shocking loss to "The Beast" at Wrestlemania, The Undertaker returned and cost Lesnar his match against Seth Rollins for the WWE Championship.
This led to weeks of intense action between the two as you could genuinely feel the animosity between them.
The match didn't quite live up to the hype, owing to Taker's advanced years and Brock's inability to wrestle the right kind of style to protect "The Deadman". The ending was also unnecessarily controversial. The two have definitely had better matches but considering the background to it and the initial excitement the pair raised, this features pretty high up.
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