F.steel A. Bendalloy combination thoughts

[strmblsd he/him]

So feruchemical steel is speed and allomantic Bendalloy is speed bubbles. So I believe u saw somewhere that a Bendalloy savant would be able to join their speed bubble onto themselves so say the were a savant with this.. they could tap speed to already go super fast then with a speed bubble hooked onto themselves they could move even faster. so would this work? Any problems with this anywhere

[Duxredux he/him]

This can have complications because the speed bubble gets jolted as it absorbs the momentum of objects passing through the boundary as the Slider runs and as the frame of reference can be shifted based on the objects entering the speed bubble. Too much interference, and it will pop the bubble. I had a question of what happens if a train with a Cadmium bubble on the front went plowing through downtown Elendel, and after some digging I found the bubble would get popped once it hit anything major. The same is likely true of a runner with an Bendalloy bubble anchored to them.

Some relevant WoBs. First one is specifically Brandon talking about how anchoring a speed bubble to yourself will introduce complications - and where we learn that this is something a Savant could do.

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Questioner

So my quick question: Can you use Identity (I love the speed bubbles!) to anchor speed bubbles to yourself?

Brandon Sanderson

Uh, this is possible. That's less a matter of Identity. What’s gonna happen there, like, the more someone uses the powers, the more familiar and intermingled with their soul the powers become, and they are able to accomplish things that others can't. This would be like a Mistborn learning to hover a coin, right, which they can do, but most think you can't. That's the sort of level we're going with.

Necarion

So a savant could?

Brandon Sanderson

A savant could totally do that. The problem is, things moving in and out of a speed bubble, there's a transference of energy. This is how we keep speed bubbles from irradiating people when light moves through them, right, red shift. And so there's a transfer of energy directly from the Spiritual Realm, which means that moving with a speed bubble, you're gonna run into that, and it's gonna be, it's gonna cause all kinds of problems, but it would be possible.

Arcanum Unbounded San Francisco signing (Nov. 30, 2016)

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Kurkistan

Okay, so I'm contractually obligated to ask about time bubbles one more time.

Brandon Sanderson

Yes.

Kurkistan

So what's up with frame of reference for time bubbles; in that obviously if you make a bubble and it's still it's not really still, like time moves differently but--

Brandon Sanderson

We deal with that a little bit in Era 2 Book 2 [Shadows of Self], where we talk about the fact that you know-- obviously the bubble is moving with the planet. So they're not-- the frame of reference is not absolute.

Kurkistan

Yeah.

Brandon Sanderson

And so we talk about sorta' the idea of mass and momentum and time bubbles and things like that.

Kurkistan

Okay.

Brandon Sanderson

For instance you can make a time bubble on a train.

Kurkistan

Oh and it stays on the train?!

Brandon Sanderson

Yes, but when you start catching stuff off of the train, it's gonna' jar each time, and it's probably going to ruin your time bubble, right?

Kurkistan

So does it get it's "anchor" from-- it's asking all the things that are within it what they think "still" is?

Brandon Sanderson

Yes. That's a good way of looking at it. Frame of reference for the Cognitive things around. Make sense?

Kurkistan

Okay, the things around or the things within it, specifically?

Brandon Sanderson

The things that it's cutting into, specifically, but yeah.

Firefight Chicago signing (Feb. 20, 2015)

So, yes, people have asked about this, but this is totally the kind of thing that's worth confirming that it's been considered.

[Speeding Steelrunner Male]

If you had a route specifically designed for this, it might work well. For example, just a long rail in the air. That way nothing new is entering the bubble, so there shouldn't be much interference.

You could also add duralumin to the mix, which should compress time even more, so you go even faster.