During the final mission of the game, when Rex Spoiler:mounts the Battle Armored Dragon Assault Strike System the theme that plays is "War", composed by Vince DiCola for the film Rocky IV, which plays during Rocky's final fight with Ivan Drago.
The description of the Dragon Blade refers to the main protagonist of Assassin's Creed III, Connor Kenway, with the lines "There've been white ninjas and African-American ninjas and Luchadores, which are like Mexican ninjas. There's a Native American Assassin, can we talk about him?"
The city destroyed in the game's introduction has the skyline of Toronto, Ontario. This is likely a joke by Ubisoft Montreal, developers of the game, in reference to the "rivalry" between Montreal and Toronto.
The Galleria 1991 shotgun is based on the one used by the T-800 in T2: Judgement Day, and gets its name from the setting of the movie where the weapon is first used, and the year that the movie was released.
While visiting the promotional Blood Dragon website, entering the Konami Code (Up, Up, Down, Down, Left, Right, Left, Right, B, A) will change the mouse cursor into a targeting reticule, enabling for every component of the site be destroyed to reveal a picture of an Omega Force soldier.
The AJM 9 is based on the automatic pistol that Robocop uses in the film trilogy of the same name. The name itself is a reference to the title character's actual name: Alex J. Murphy. The idle animation for pulling out the weapon is Rex spinning it in his hand, a motion that Robocop became known for.
During the final mission of the game, the Spoiler:Battle Armored Dragon Assault Strike System exclaims "IMMA FIRING MAH LAZOR." This is a reference to an internet meme which of the exact same wording.
Towards the end of the game, after Rex Spoiler:picks up the Killstar, he will exclaim "I got the touch... I got the power..." This is a reference the 80's song "The Touch" by Stan Bush, made popular as the theme tune to the animated Transformers movie.
During the mission Summon The Plague, as the doors of the gate open, it will exclaim, "Test your might!" This is a reference to the Mortal Kombat series, which has a popular minigame of the same name.