Infinity Mode

∞ Mode, commonly referred to as Infinite Mode or Infinity Mode, is a game mode in Dead Rising that can be unlocked by completing Overtime Mode and achieving the True Ending. It is virtually a sandbox mode where the challenge is to keep Frank alive for as long as he can. It is the only game mode where the achievements 5 Day Survivor and 7 Day Survivor can be earned.

Description
Frank's health will decrease steadily by one health block every one minute and forty seconds, i.e. 100 seconds. The PP bar is replaced by a countdown meter that indicates the remaining time before a health block is depleted. When all health blocks are depleted, whether by degeneration or by other sources of damage, Frank will die and the time survived will be recorded.

To help Frank prolong his survival time, food can be found in various locations in the Willamette Parkview Mall. However, any food item that has been taken from its original place will not respawn after Frank leaves and re-enters the area. In addition, areas with food that spawn infinitely are disabled. Thusly, Frank can only survive for a limited amount of time before he runs out of food.

There are several other limitations of ∞ Mode: progress cannot be saved until the game ends after Frank dies, and Frank's camera and watch have been disabled.

Survivors and Psychopaths
Nearly all survivors and psychopaths appearing in 72 Hour Mode can be found in ∞ Mode. They will appear in different locations and times within the first eight days of the game. All survivors and psychopaths are hostile and will attack Frank with their weapons. Upon being killed by Frank, they will drop a cardboard box that opens to give several weapons and food items; however, if they are killed by damage dealt by themselves or an external source such as the zombies, they will not drop the cardboard box. While the psychopaths are equipped with their signature weapons and attacks, the survivors are armed differently.

For information on spawn times and locations for all survivors and psychopaths appearing in Infinity Mode, see Infinity Mode/Survivor Locations.

Tactics
Frank's survival time can be prolonged by utilizing several tactics. They vary from increasing the healing ability of food items that Frank can acquire, and by reducing damage he takes from zombies and hostile survivors.

Raw foods such as raw meat should be cooked in stoves to prevent them from turning spoiled, and frozen foods such as frozen vegetables should be eaten before they melt.

There are three books that can increase the health restored by food items: Health 1, Health 2 and Survival. When all three books are kept in the inventory, food items can heal up to three times the health blocks they would normally restore.

Certain areas in the game are inaccessible by zombies, and by remaining in such locations, Frank can avoid unnecessary damage by being swiped or grabbed by zombies.

Rationing can be carried out to ensure that each food item eaten will restore the maximum amount of potential health gain. All food items in the area should be eaten or stored in Frank's inventory before leaving the area to prevent wastage of scavenged food.

It is generally a good idea to have the Real Mega Buster equipped to quickly eliminate other survivors. The Mega Buster can be unlocked by completing the Zombie Genocider achievement (killing 53,594 zombies in one playthrough).

Whatever you do, DO NOT ENTER OR EXIT the FOOD COURT from 4:05:00 to 4:23:59 or else the game will FREEZE on the loading screen.

For information on spawn times and locations for locations inaccessible by zombies in Infinity Mode, see Infinity Mode/Safe Spots.

Trivia

 * If the time was equivalent to the real world's, damage would happen every 1200 seconds or every 20 minutes; of course, this is certainly not consistent with reality, as deterioration would happen much later from lack of food.