lots of random worldbuilding thoughts just for fun, teleportation
I think a sort of relative spacial shifting ability (through magic/tech/superpowers) would be a pretty interesting and not too OP form of teleportation. I'm imagining that you could teleport (or "shift") over small distances relative to your position in any direction, keeping your momentum.So you could e.g. teleport behind a wall, or into / out of a stationary vehicle, but a moving one would be dangerous as you'd reappear next to it moving the same speed it was going.
Probably this would have some sort of energy cost exponentially growing with the distance, limiting how far you could go and how quickly you could go again, as it has to recharge somehow. These parameters (capacity, efficiency, recharge rate) could be dependent on all sorts of factors, like the tech specs, or training, or how skillfully a spell is cast for example.
When going upwards, the change of potential energy would have to be incurred on top of the cost of teleporting over the distance. This would also mean that going downward might be cheaper than level. Maybe this extra cost would be irrelevant in comparison tho, or it would have to be scaled by making the energy conversion (much) less efficient.
Even on a larger scale of distance, it would still be limited in usefulness by the fact that the earth is rotating, and at different speeds depending on the latitude. Although this could maybe also be used as an advantage by a skillful user or with precise calculations.
You could also use this spacial shifting to move around faster or jump farther without it being obvious how, by repeatedly shifting tiny distances forward instead of making a bigger shift at once. (Kind of like with Projection Sorcery in JJK, but without building up speed.) This would also be cheaper because of the exponential cost.
And shifting around back and forth very quickly could be used to "blur" yourself (think The Flash). And it'd be a big advantage in fights of course.
Whether it could only apply to your whole body (or other objects) at once, or also to individual limbs without, uhh well, severing them, would be another interesting thought to explore.
(I'll not get deeper into it only affecting your body and not clothes, like with Hughie in The Boys; I think that concept gets dull pretty fast. Unless it being kinky would be the point I guess.)
Anyway, this kinda thing is just really fun to think about, and could go on endlessly!
This time it was prompted by me rushing to catch my commute train home, and (like pretty often) thinking how cool it would be to just shift into the bus that was just leaving, or any vehicle going my direction, and hitching a ride for a few hundred meters to save time.