This question is based on the time travel mechanic discussed in my previous question The Tricky Trouble with Two Time Travelers. I'll lay out the rules that I've decided on so far:
- Certain people (you can call them rewinders) have the ability to travel back in time (the rewind power).
- When a rewinder uses her power:
- First she activates her power. The activation is a purely mental action. It takes negligible time, and can be done reflexively if she is mentally prepared.
- She then selects a point in the past. You can regard this selection as happening instantaneously. The selection is quite accurate: a novice rewinder can control the amount of time rewound to within around 10%, and some practice will improve this to 1% or better.
- At this point, the physical state of the universe is rewound, set back exactly as it was at the chosen moment. Nothing is special: even the rewinder's body returns to the position and condition she was in at that moment.
- However, crucially, the rewinder retains her memories of the possible future she experienced (the period between the current moment and the moment she activated her power).
- The length of time that can be rewound is limited by a sort of mental stamina.
- For this question, assume that each rewinder has around two minutes of stamina.
- A rewind uses an amount of stamina equal to the amount of time rewound, plus around a second of overhead.
- A rewinder's stamina recovers in realtime. That is, she regains one minute of stamina for every minute that elapses.
- Other rewinders can notice a rewind:
- If, at any point, a rewinder's experience in the present differs from their experience in a previous "possible future", she regains her memory of that alternate future.
- Recall of a possible future is only triggered by differences that she could notice. For example, if a page of text was worded differently in a possible future, she would need to read the text to trigger recall, simply looking at the page would not be enough.
- She is not forced to relive those memories. Unconsciously, she gains a déjà vu-like knowledge of how events unfold in the previous possible futures. She can also consciously review these memories like any other. (Except that in this case she remembers two or more different sequences of events where a muggle would remember only one.)
- The rewinder's brain gives precedence to recall of possible futures that are more important to the rewinder.
At this point, some examples are in order.
- Alice and Bob, both rewinders, are conversing over lunch. Alice knocks her cup off the table, and it shatters on the floor. She rewinds thirty seconds. The thirty seconds before the cup shattered is now a possible future. She moves her cup away from the edge of the table. As soon as Bob notices Alice move the cup (something that did not happen in the previous possible future), he remembers her knocking the cup off the table, and their entire conversation from the possible future. You may find it useful to think of the rewind as "ending" the current timeline and "branching off" a new timeline in the past, like in this diagram:
- Alice and Bob are eating lunch on opposite sides of the break room. Bob has his back turned to Alice. Alice knocks her cup off the table, which Bob does not hear. Before it hits the floor, she rewinds thirty seconds. This time she moves her cup away from the edge of the table, and eats her lunch for the remainder of the thirty seconds. Since Bob is/was looking the other way, he will remain unaware that a rewind happened.
- Same as above, except this time after rewinding, Alice picks up the cup and throws it in the trash next to Bob. As soon a Bob notices Alice throwing away the cup, he remembers the possible future where Alice does not throw away the cup. However, since Alice rewound before the cup shattered on the floor, Bob is unaware that Alice knocked the cup off the table in the possible future.
- This example is posted as an answer due to its length (this question is already long enough). I've tried to include every mechanic that people have asked about, so be sure to take a glance.
How would a rewinder use her power in hand-to-hand or close-quarters combat against another rewinder? Both strategies and examples are OK. You may consider the case where she initially does or does not know that her opponent is also a rewinder. You can discuss how she would recognize that her opponent is rewinding, or how she would conceal her rewinds from her opponent.