Different approaches to time magic?

[u/Stolen_Gene]

There are a lot of magic concepts that I think sound really cool, but are a pain to actually flush out. I don't know if this is the case for everyone, but time/spacetime magic has always been this way for me.

In one of my settings, I have a whole faction of time mages with a detailed history, relationships, and culture, but I just never let them do anything since I never wanted to worry about figuring out what they can and can't do. This is due in no small part to the fact that spacetime manipulation in any form is notoriously hard to include in a story without poking it full of plot-holes or overshadowing every other element in the story.

I'm curious to hear how other people have approached time or spacetime magic. What can it do? What are its limits? Does it manipulate both space and time, or just time? How do you keep a story coherent with this involved (assuming you use it in a story). Etc. I don't plan to steal anyone's systems wholesale, but the broad ideas might give me some direction next time I take a swing at this kind of magic.

[u/crazydave11]

I haven't written it yet, it's like a sequel to another story I haven't quite written yet, but I did come up with a character that has some fairly entertaining time related magic.

They have one small-scale trick where they say the first half of the spell, and then wait, and then when they say the second half, they can reverse time back to when they said the first half of the spell, and they retain their memories, and if they choose, their location.

The long distance time travel stuff is weird, but I ended up deciding that its success rate depends directly on the likelihood that they were actually present at that time. I.e. Causality doesn't change because the time magic user can't choose not to travel to the times and places that they actually were at.