The Dead Rising series is a collection of zombie apocalypse survival games developed by Capcom. The leader of the initial project, Keiji Inafune (perhaps best known for his work on the Mega Man series), played a heavy role in the first Dead Rising's creation. Players can use any range of zany weapons found all over the game for use.
The Importance of Time
What sets the Dead Rising franchise apart from other open world games is the importance of time. The Dead Rising franchise is built in such a way that you cannot accomplish everything in a single playthrough. You're on a tight schedule that forces you to manage priorities. The games' levels are divided into different cases. Each case starts and ends at a specific time (for example, a case is only available between 8pm and 9 pm). The time also factors into the story. You had 72 hours in both Dead Rising 1 and 2 to survive until help arrived.
Each case is thus on a timer. You can choose which cases you wish to do but if you miss a case that is essential to the main story, only other main story cases will be failed. The game also throws out specific situations where you have to make choices since there is not enough time for you to do everything. For example, in Dead Rising 2, you had to give Zombrex to Katey every 12 hours but a survivor needs it to survive. Do you keep going with the main story and give zombrex to Katey or do you give it to the survivor to earn extra PP? This is more of an issue when trying to gain the games notoriously difficult achievements, where it is actually impossible to gain them all without multiple playthrough's, unlike in the previous example where you can search for extra Zombrex and save both Katey and the survivor.
The Dead Rising franchise has always encouraged multiple playthroughs, for multiple reasons. The Dead Rising franchise has a level system where you gain PP (Prestige Points) for doing specific things (saving survivors, killing a certain amount of zombies, defeating psychos). Gaining levels lets you carry more weapons and have more health. Everytime you die, the game asks you if you'd wish to start over but keep your current level (the game does not scale to your level).
Seeing that your stats carry over when you start over, there is a good reason for the player to start a new game if they get stuck. Survival at the beginning of the game can be rough, especially against the psychos. Restarting multiple times ato grind levels can make the game easier. Also, the fact that the timer only lets you do certain things means you won't be able to see everything on your first playthrough. The series also features multiple endings, with one true ending for completing all the case files and sometimes overtime as well.
Dead Rising features a staggering amount of weapons, many of questionable combat effectiveness. These included CD's, jewels, giant teddy bears, and shopping carts. The series takes it's oddity so seriously, when in the first person mode you can even spit on zombies. Dead Rising 2: Case Zero was the first game in the series to add the combo weapons feature, allowing the player to combine items to make even more ridiculous weapons. For example, a pitchfork added to a shotgun makes a " Boomstick". This is useful for impaling zombies and then blasting them to bits in the air, like red confetti. The combining of weapons to make more effective weapons has become one of the distinctive and defining features of the series.
Additionally, being trapped in civilian centers of commerce for both games means two word's: Clothes Shopping! The player is encouraged to combine hats, sunglasses, and shoes to make the most ridiculous (or snazzy) outfits they desire.