The late-night host, whose NBC show is nominated for best variety talk series, has done everything from smashing a raw egg in his celebrity guests' faces to slapping them with a giant prosthetic hand.
Game rules: Fallon and his celebrity guest go head-to-head as they put on lip sync performances of popular songs. The song selection is kept a secret between both competitors.
Memorable opponent: Emma Stone won the battle by a landslide when she perfectly lip synced the lyrics to Ludacris' verse in DJ Khaled's "All I Do Is Win." The recurring Tonight Show segment became so popular it landed its own series on Spike in February 2015.
Game rules: Both players take turns opening a box (out of the other person's view) with a mystery item inside and describe the item to their opponent. They can either choose to tell a lie or the truth about what's inside their box, and the other person must guess which it is.
Memorable opponent: Jennifer Lawrence, who appeared as a guest on the show in May 2014, shut Fallon down for attempting to tell her what she thought was an elaborate lie. When the host told her he had a Backstreet Boys action figure inside of a box filled with Hershey's kisses, she told him, "If it's not the truth, you're a sociopath."
Game rules: One player puts on headphones playing loud music, while the other reads a random phrase off of a card aloud. The player wearing the sound-blocking headphones then tries to guess what the phrase is by lip-reading.
Memorable opponent: Blake Shelton mistook "pumpkin spice latte" for "my pee-pee is stretched out" and called foul when Fallon guessed Benedict Cumberbatch. "There is no way. That doesn't even mean anything!" Shelton, who hadn't heard of the Oscar-nominated actor, said. "That's a person? I've never even heard of that."
Game rules: An egg carton filled with a dozen eggs — eight hard-boiled and four raw — is brought to the table, and both players take turns carefully choosing eggs and smashing them against their heads. The unlucky player who chooses two raw eggs loses.
Memorable opponent: Anna Kendrick was the first female guest who got messy and played the game. The Pitch Perfect actress got the raw egg treatment just once and played it off as if the yolk was hair conditioner.
Game rules: Fallon and his opponent play the card game War, and the loser of each round is splashed in the face with a glass of water. The first person to empty five glasses of water on the other player wins.
Memorable opponent: Jake Gyllenhaal didn't hold back during his match with the host, dribbling water on top of his head, down his back and declaring "This one's for my family!" as he splashed water across Fallon's face.
Game rules: Fallon and his guest play a game of blackjack where the loser gets slapped with a giant prosthetic hand.
Memorable opponent: Kevin Hart didn't bother to go easy on the host, hitting him so hard across the face that a stunned Fallon jokingly claimed he lost his hearing.
Game rules: Fallon and his guest are each given five random words and tasked with working them into a casual conversation with each other.
Memorable opponent: Ricky Gervais couldn't contain his laughter when he asked Fallon, "Do you have a nickname for your penis?" in an attempt to gear the convo towards his last remaining key word: squeegee. Fallon's reply? "Keanu Reeves."