Arsenio Hall vs. Aubrey O'Day (Season 5)
And then there was the blowup that preceded the Hall-Lampanelli fight. O'Day had been taking credit for her team's successes throughout the show, and by this midway point of the season, Hall had had enough and called her out on it. Donald Trump acknowledged he'd recognized the same behavior in her, and her teammates said she should be fired if her team lost (they didn't). Trump even chastised her for turning on the waterworks. O'Day felt her teammates, especially Hall and Clay Aiken, had ganged up on her, so when they left the boardroom to let Trump deliberate, O'Day got in an elevator and split, leaving Hall to continue ranting about O'Day and viewers to wonder if O'Day had quit the show.
NeNe Leakes vs. La Toya Jackson (Season 4)
"Real Housewives of Atlanta" star NeNe Leakes let La Toya Jackson know she was not impressed with her family heritage, and that her last name was the only reason she was on the show, anyway. To her credit, Jackson remained relatively calm throughout the verbal tussle, with Leakes accusing her of disappearing throughout their task -- even going so far as to call Jackson "Casper the Ghost" -- and Jackson calling Leakes a loud bully. The reality star's parting shot to Jackson: "You need to play your age, and not 12. You are an old lady."
NeNe Leakes vs. Star Jones (Season 4)
This diva showdown is one of the series's most notorious moments, as Leakes, who'd grown increasingly frustrated with what she labeled as bossy and manipulative behavior by Jones, told Jones she would take her down. Jones claimed to Trump that she had nothing but good intentions when she suggested that Leakes be the week's project manager for the women's team, but NeNe was having none of it. "You pushed the last button in me, Miss Star Jones," Leakes said. "You talked a good game, but now bring your street game … now, where's Barbara Walters, Miss I'm So Educated? How educated are you on the street?"
Meat Loaf vs. Gary Busey (Season 4)
It's easy to understand how looney Gary Busey could test the patience of even the most laid-back individual, but during a Season 4 task that required each member of the men's team to have their own art supplies, Meat Loaf thought Busey had lifted some of his, and he came at Busey like -- yes, sorry, we have to say it -- a bat out of hell. So angry and loud were Meat's threats to Busey that teammate Mark McGrath had to physically hold the rocker back, while Busey looked on cluelessly. "You look in my eyes! I am the last person in the f-----' world you ever f-----' want to f--- with!" Meat screamed. PS -- The MIA art supplies were in a bag Meat Loaf had misplaced.


