I think I know how the new ability is going to work. (spoilers)
So, with the Critic previews we've seen today, we know about the new "power", Autobuild, which will allow us to Save and drop "blueprints" of constructed items made with Ultrahand.
This is GREAT as it means we get a chance to really experiment, build and refine things we really want, rather than just kind of macgyvering something out of what's in the area (though I'm sure theres going to be a lot of that as well).
The question is though, HOW does this really work? Part of it is obviously the Zonai Capsules we see several times in the previews.
https://preview.redd.it/jdapy9cz3aw...ed&s=0eb63746d0faf0286b4adddbc2c399084af11f9f
These will likely be pulled directly from our inventory when using Autobuild. But that begs another question; what about items you don't have, or ones that AREN'T Zonai Devices, and thus don't have a capsule?
Can you simply NOT build those Blueprints? Personally, I think this is EXTREMELY unlikely. Why? Because we've seen lots of examples of Ultrahand constructs with non-Zonai parts. And likely, MOST constructs are going to have some kind of non-Zonai part in it.
So how do THOSE work? Well, I think I know how.
In a few previews we see some constructs that look distinctly... different, compared to others
https://preview.redd.it/4r6szjo14aw...ed&s=ff8b2eb3f6642b621433927325d0be1ebd129cae
Right away you can spot WHAT makes them so weird compared to other constructs
https://preview.redd.it/6ruem5u24aw...ed&s=9f0412905487f19a5af1f165f461c51d2f279989
But what's the reason for that? If Autobuild can just auto assemble all the parts, what is with the overwhelming green skin? I think the answer lies with ANOTHER new item we see in the previews.
Zonaite.
https://preview.redd.it/q7kzvb344aw...ed&s=f565cb787157620a45e4d725302342ca5f390b6e
From the description, we can assume that Zonaite plays an important rule in the game and in Zonai technology as a whole. But what use is it, mechanic wise?
The first awnser that probably pops into people minds is as a currency for upgrades like Iron ore and other ores in BotW. This is highly likely.
Some have even speculated that it is the currency used at the "gatcha" machines to buy Zonai Capsules. This is also another likely possibility.
But I want to propose a THIRD idea.
What if Zonaite is used as a "Filler" material in Autobuild?
It would work something like this.
Every item has a set Zonaite "value". Probably as cheap as 1 for something like a wood plank or stone slab, with more expensive for complex items like Zonai Devices.
When you "Save" a Blueprint with Autobuild, its assigned a cost based on the Sum Zonaite value of all the Objects used to make it.
When you then go to "Rebuild" the Blueprint, the game looks at the Items you have in your inventory, then subtracts their value from the cost of the Blueprint.
The remaining value is then "paid" with Zonaite instead.
These "Copied" parts are the green parts that we see on the weird looking constructs.
This is further supported by a few clips where we can see Builds that have a mix of "Copied" and "Real" parts.
https://preview.redd.it/346ajol54aw...ed&s=c9615f4784792756f6d22a1371dcf7f74c3ec455
Likely this has some restrictions of course. The biggest being its unlikely these "Copied" part can be removed or adjusted, unlike something built by hand. I.E they're fixed in place.
This would also solve the issue of someone just spawning a thousand cars from nothing.
All your Rebuilds would be limited by your Zonaite supply.
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Overall, I think if this really IS how they've done it, its a great idea and I can already think of a dozen ways to use it.
For instance, imagine building a bunker to block boss attacks, or building something designed to crush enemies by pushing it down a hill.
Its got a LOT of potential.