The Double Lariat is a reference to Zangief's Double Lariat move from the Street fighter series.
Contributed by ProtoSnake
The Somersault Kick is a reference to Guile's Flash Kick move from the Street fighter series.
Contributed by ProtoSnake
The achievement "Zombie Genocider" is achieved after killing 53,594 zombies, the population of Willamette Colorado, where the game takes place.
Contributed by nolanms1
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In early beta footage for Dead Rising, finding survivors during side missions would momentarily freeze all activity while the camera focused on the found character(s), and the message "Missing Person Located!!" would appear on the screen. The time allocated per side mission was also represented with a countdown timer, rather than the descending bar used in the final game.
Contributed by TheBigD999
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In the shop called "In the Closet" is a a t-shirt with a woman on it. In the US version of the game, the woman is topless, whereas in the European version she is wearing a bra/bikini top.
Contributed by DeerBoarDude
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In pre-release screenshots, Isabella is seen holding a Sniper Rifle. In the final game, only her brother Carlito wields a sniper rifle.
Contributed by ClaudX
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In early screenshots and trailers, Frank is seen reuniting an old couple at the mall entrance. In the final game, he reunites them on the rooftop.
Contributed by ClaudX
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During development, Frank's appearance was originally much rougher, and he had a different voice actor.
Contributed by ClaudX
The rights-holder for George Romero's film "Dawn of the Dead" sued Capcom for plagiarism. The lawsuit claimed that Dead Rising ripped off Dawn of the Dead, and listed the following similarities between the two titles:

•Both works are set in a bi-level shopping mall.
•The mall has a gun shop, in which action takes place.
•The mall is located in a rural area with the National Guard patrolling its environs.
•Both works are set in motion by a helicopter that takes the lead characters to a mall besieged by zombies.
•Many of the zombies wear plaid shirts.
•Both works feature a subtext critique of sensationalistic journalism through their use of tough, cynical journalists with short brown hair and leather jackets as a lead male character.
•Both works feature the creative use of items such as propane tanks, chainsaws, and vehicles to kill zombies.
•Both works are a parody of rampant consumerism.
•Both works use music in the mall for comedic effect.
•Dead Rising's use of the word "hell" references the tagline for Dawn of the Dead's release ("When there's no more room in hell, the dead will walk the earth.").

The suit was dismissed in court.
Contributed by Makarov
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Mega Man X's armor is obtainable in game via certain achievements and hidden locations. To complete the look, two versions of his Mega Buster are also available. One is a toy but killing 53,594 zombies and unlocking the "Zombie Genocider" achievement grants the "Real Mega Buster".
Contributed by Funland47
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In Colby's Movieland is a Megaman 2 cardboard cutout.
Contributed by Funland47
It's possible to find masks of Servbots from the Mega Man Legends series.
Contributed by Psychospacecow
The store "Child's Play" has a statue of a servbot from Mega Man Legends.
Contributed by Psychospacecow
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Adam The Clown's death is censored in the Japanese version. In the North American/European version, he is gushing blood after you kill him. This was changed so that barely any blood is shown.
Contributed by gamemaster1991
The sandwich store "Jill's Sandwiches" is a reference to a scene in Resident Evil 1, when Jill is trapped in a room, only to be saved by Barry who exclaims, "You were almost a Jill sandwich!"
Contributed by Dazz