WWE SummerSlam is seen as one of the biggest events of the year. Since WrestleMania 36 wasn't able to include many of the Superstars who Vince McMahon may have wanted at the Showcase of the Immortals, SummerSlam could be the biggest show this year.At present, there are a number of WWE Superstars on the sidelines whilst the COVID-19 pandemic continues to cause issues for WWE, as well as others who are still on the outside waiting to make their return from injury.SummerSlam would be the perfect event for many Superstars to return since the global pandemic seems to be settling down around the world and fans will hopefully be able to make their return to arenas by August.#5 Brock LesnarBrock Lesnar was defeated by Drew McIntyre back at WrestleMania this year and hasn't been seen on WWE TV since. The former Champion has instead decided to sit out the last few months and remain safe with his family whilst the pandemic has taken hold.It's a strange situation because Lesnar is the kind of star who would be looking to get even with McIntyre following his victory, much like when Seth Rollins defeated him at last year's WrestleMania.If McIntyre continues to dominate on Monday Night RAW, then it's easy to see Lesnar making his return at SummerSlam so that he could become a roadblock. It's also easy to see The Beast Incarnate setting up a match for himself for the next Saudi Arabia show (if Crown Jewel happens later this year) whilst he is there.SummerSlam is also expected to be the first WWE show since March to have an actual audience in attendance, which is something that could easily sway Lesnar to making his return to the ring much sooner than expected.