[@Baklava] I do believe the ancient flower is only acting as an oil/lubricant, but you can decide whatever you wish for this of course. As well there is one ancient robot that functions without a time shift stone, it is in the temple under the goddess tower.

Well the most basic gist is prototyped ancient robot, in the LD-00 set not the 301 series. Going for a sort of iron giant character

It's name is Noi, a name it gives itself when he misreads No.1 on his blueprints. While future LD-00s would be made light using a skeletal design Noi is very bulky with a thick layer of armor over his frame. This greatly reduces his speed, but does grant him astounding durability. Other features added to future models like a highly detailed face and decorative armor were never created for Noi. His head is essentially a plate helmet welded onto a sensor array.

Noi is equipped with a large hammer intended for both defense of the worker robots and for assisting them with mining.

Noi is not the most complex of characters mentally while somewhat aware like most of the ancient robots he isn't a third as intelligent. He understands hylian and has a basic database of information on the world, but even then his actual intelligence is akin to a child. There is a general sense of morality given to him by the rules he has to obey in his programming.

As for how to fit him in. I think there is plenty of possibility for Noi to be slipped in without any crazy changes. Since the LD-00 robots don't seem to need maintenance he could be off functioning in some sort of long abandoned mine despite all others having broken down something akin to Wall-E. If you want maintenance to be required then I'd suggest Noi runs off something different that was rare then, but is more common now if thats possible, a sort of ironic twist the material was ignored because it would be so hard to get, and yet because it was so hard to get it now is comparatively plentiful.