Area Mex Command
The Area Mex command queues construction of metal extractors in a given area.
The individual constructions are ordered from the nearest mex to the builder in the area to the farthest, disregarding obstacles - for this reason it may be better to queue several Area Mex orders to guarantee an optimal builder walk path.
Holding ALT while placing an Area Mex order will place 4 solars around each mex in the area. This protects the extractor and provides Overdrive. When queued on sea, tidal turbines are used instead of solars.
You can use the ALT modifier for adding Solars to existing metal extractors as well.