I had this idea for an RP that starts 24 hours before the world ends. The ground cracks apart, and things disappear into the endless void. People that fall into the void are never seen again. At the end of the 24 hours, everything fades, and a new day dawns, or rather, the same day. The RP would continue in 24 hour cycles, with no characters remembering the previous cycles. Any physical damage characters took during the previous cycle still effects them (if someone is stabbed during one cycle, they will still have the wound during the next, but they wont remember being stabbed). Any characters who died will stay dead, and any important objects that fall into the void will stay missing.