Referring Cena, some examples. Wrestlemania 1 main event, Hogan slamming Andre, HBK winning title first time, Mankind falling from cell, Mankind winning title on Raw, Austin not quitting at mania during the sharpshooter while bleeding, his KOR promo, Undertaker mania streak, CM Punk pipe bomb, Rollins mania cash in, even his second one, Rollins turning heel on the shield, the shield debut, Rock vs Hogan, and maybe some I'm forgetting. But all of those are groundbreaking moments, lot of them are arguably top five or ten in history.
I say that because i can't think of a Cena moment that is in that group. Maybe you younger folks that grew up with Cena know better than me.