During the opening sequence as the player is walking through the halls of the building, he sees a man carrying something into a door for a brief moment. The character is Doug from The Walking Dead Episode 1. The player has to save either him or a female reporter named Carley from zombies. Most people save Carley over Doug, explaining why he gets the cameo.
During the opening sequence when the player meets Brock Sampson from Venture Brothers, Bandit was thrown out of the room. Brock says it was a good game to see him next week-- that character was a bandit in The Walking Dead: Episode 2, in which he shoots another bandit for stealing food than later gets shot by Lily in The Walking Dead: Episode 3 while Lee distracts him.
Complete a tournament with the following themes in place to unlock the corresponding special endings:
Army of Darkness theme
The player is given a potion; three sips of which will put them to sleep until the next tournament. Upon taking three sips the host reconsiders if it was two or three sips. The player blacks out to awaken at the table with everyone (including GLaDOS who is a machine). Sam says "Hope you like alien invasions". The player blacks out and Brock says "I told you these fake beards were a bad idea". This is a reference to the alternate ending to Army Of Darkness, where two sips of the potion has Ash waking up in a cave in his own time, however he takes three sips and wakes up to a post-apocalyptic world.
Borderlands 2 theme
The host congratulates the player and says he has a great deal of experience points and a Borderlands 2 objective complete menu appears, reading "Goal - Defeat 4 worthless Skags, Experienced Earned:1, Money earned - 100,000".
GlaDos asks if the player thinks they are clever for winning but to consider their opponents - a steroid freak with rage issues (Brock Sampson), a horny robot (Claptrap), a cripple (Ash Williams), and a dog (Sam), and even then the player needed luck. She then says she would like to see how the player would perform under difficult conditions then drops several Portal turrets which are aimed at the player. Before saying she was just kidding and that she would never kill the player... in public, the turrets will start playing techno music. This is a reference to the end of Portal 2 where Chell is confronted by three turrets while trapped in an elevator on the way to the surface, but instead of attacking they begin performing a massive opera.
Sam and Max 25th Anniversary theme
Max appears and gives the player a huge kiss, leaving a black lipstick stain on the screen. Sam remarks that Max does not even like whatever gender your characer is. Max ignores Sam and asks you to call him.
Venture Brothers theme
The host insists Brock Sampson do the Team Venture sign. Despite his reluctance, he eventually gives in and a television show-style episode title appears called "The Wagers of Sin Are Doom".
The following themes remove the first player eliminated in the corresponding way:
Army of Darkness Ash and Sam
Max read the Necronomicon wrong. It flies around the room then devours the character who busted.
Borderlands 2 Ash
GLaDos says Ashley Williams has been eliminated or he will be in a minute. Steve (the character on the cover of Borderlands and Borderlands 2) drops down on the stage and opens fire with a confetti rocket. Ash gets knocked on the ground. Ash complains that if they wanted him to leave they could have just asked.
Borderlands 2 Brock
Steve drops down and shoots Brock with the confetti cannon. Brock says to excuse him and heads off-screen. Steve can be heard saying a nervous "Heyooo" before the sounds of pummeling are heard.
Borderlands 2 Claptrap
Claptrap imitates the demise of Jesse James telling Steve to do what he has to do. Steve shoots Claptrap with a confetti cannon and lets out a mournful "Heyoooo", which Claptrap dismisses as he gets up and calls Steve a drama queen.
Borderlands 2 Sam
Steve puts a hand on Sam's shoulder. Max growls and Sam says "You crack me up Steve", then the three of them head off to hang out.
Portal Sam and Ash
GLaDOS opens a portal underneath them and another on the wall in the back of the inventory.
Sam and Max 25th Brock
Max leaps on Brock's head and begins chewing on him. Brock takes no notice other then mild annoyance.
Sam and Max 25th Sam
The time machine from Sam and Max Season 2 appears and another version of Sam and Max asks them to join them on an adventure.