Brick Joke: Barney is hesitant to take part in the game show and asks Norma and Pugsley if they're sure they don't want to just get a mug for Courtney instead. As it turns out, no one has ever actually won Hox's Castle, so when they end up winning thanks to Temeluchus' presence, they are awarded with... a mug.
Christmas in July: It's right there in the title; Phoenix Parks has a celebration every year called "Christmas in July".
Clone Angst: When Hox pushes Barney down the stairs and causes him to get struck by lightning many times as a "Sudden death", Norma and Pugsley use the lifeline to bring him back. Instead of reviving him, it makes an exact copy of him with all his memories, while his dead body turns to dust. Upon realising this, Barney decides he will need to see a therapist about it.
Death as Comedy: Barney dying from falling down the stairs and being struck by lightning is played for humour, with his dead body having a comical expression with X's for eyes, and Courtney finding the show more entertaining. Barney's reaction upon seeing his dead body turn to dust in front of him after the lifeline creates a new body for him is to calmly state he'll need therapy, and the prize they get for winning is a mug that says "My friend died on Hox's Castle and all I got was this lousy mug".
Did I Mention It's Christmas?: The fact that it's "Christmas in July" is only brought up at the beginning and end of the episode, which revolves around Barney, Norma, and Pugsley taking part in a game show in Courtney's place since she can't go herself.
Fluffy the Terrible: The last round of the game show is called the "Chamber of Cuddles". That's because it houses a giant crab whose name is Cuddles.
Literal Metaphor: The "Lightning round" involves actual lightning that the trio have to avoid getting hurt by. After this comes "Sudden death", where Barney is killed very suddenly.
Sadistic Game Show: Hox's Castle is this; the rounds are extremely difficult, and Hox intentionally tries to make it difficult for Barney, Norma, and Pugsley, and presumably any other contestants. When they manage to get past two rounds, he pushes Barney down the stairs, where he is struck by lightning on the way down and dies, and the lifeline doesn't revive him but rather creates an entirely new Barney with all his memories. It turns out that no one has ever actually won the show before, with most people not even getting past the first round, and they don't even have any prizes to give when Hox allows them to win after he realises that Pugsley is possessed by demon royalty.
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