Batman Gambit: The whole episode turns out to be one. Splinter reveals at the end that he teamed up with Piebald to scare the turtles into admitting they lied. His rationale is that they only learn lessons the hard way.
Decoy Protagonist: It seems like Mikey is the star of the episode, but he's captured just over halfway through, leaving Leo with the spotlight.
Leo: I know you're not talking about the thing we talk about never talking about.
Dwindling Party: The turtles are captured until only Leo remains.
Failed a Spot Check: Subverted. It seems like Splinter hasn't noticed that the turtles replaced his goldfish with a rock. He later reveals that he saw through it immediately.
I Want My Mommy!: At one point, while running for his life, Leo bursts through Splinter's door yelling "DADDY!"
It Was Here, I Swear!: Mikey finds some threatening graffiti saying "You flush me, I flush you" on his bedroom wall but when he calls Leo to have a look, it's gone. He even says the trope word for word.
Laser-Guided Karma: Discussed. Piebald wants to flush the turtles the way they flushed her, which will force them to live in the sewers as mutants. Leo pokes a hole in this by pointing out that that's their situation already.
Nice Job Breaking It, Hero: Two in a row. The first involves literally breaking something in the form of Piebald's fishbowl. The second is when the turtles put Piebald in the toilet, which they inevitably end up flushing.
Paper-Thin Disguise: The turtles replaced Splinter's Piebald with a rock. Piebald calls them out on how lazy this was.
Properly Paranoid: When Mikey sees the graffiti mentioned above, he immediately assumes that Piebald has come back for revenge. He's right.
Replacement Goldfish: Leo states that after they flushed Piebald, they got another goldfish so Splinter wouldn't find out. We later see that they just put a rock with some google eyes in Splinter's fishbowl.
Vertical Kidnapping: Piebald captures Raph and Donnie by lifting them up with her fishhook.
Ambiguous Situation: Leo falling on Donnie during the Fridge Balance challenge. Leo insists that it was an accident while his brothers think it was on purpose.
Big "WHAT?!": Offscreen example. Raph and Mikey claim they did this when Donnie returned for the final game and re-enact their reactions.
Broken Win/Loss Streak: Donnie ultimately wins the games this year, ending Leo's five-year streak.
Failure Montage: We are treated to one of Donnie failing in various game events, one of which involves smashing a watermelon, which he can't do no matter what he tries.
Fan Disservice: Splinter once again shaves himself. To make it worse, he oils himself up this time.
Fan of the Underdog: Raph and Mikey eventually start rooting for Donnie in the games. One: because he’s always had a bad losing streak in the games and two: because Leo’s constant gloating over being the lair games champion made him insufferable.
Game of Chicken: One of the games is to see who wusses out of being covered in goo first.
Mala Proper: When Leo is accused of sabotaging Donnie, he compares the accusation the "Salisbury" Witch Trials. Donnie lampshades this.
Mockumentary: April is documenting the games this year.
The Olympics: The titular Lair Games are the turtles' version of this.
Pyrrhic Victory: When Donnie wins the games, he gets to crash in Leo's room. Leo doesn't mind since Splinter's room is right above, so Donnie will have to listen to him snore.
Tiebreaker Round: When Leo and Donnie tie for the final game, the rules state Splinter gets to decide on a tiebreaker game. His game is that they must catch him while he's oiled up.
Unsportsmanlike Gloating: Leo is the five-time champion of the games and he's anything, but humble about it.
