An ancient city is buried under volcano on Mosconi in Space/M12.

Eternal Volcano can be searched once Flame Incinerator has been defeated (F2493 A2215 S2195 L2397 /E25.6M).

As for Tartarus Gate in Space/M07 the search can be performed directly in-situ in Space/M12 or through the Special Task tab in the Tactical Hall in Eden.

To perform the search, you click on Dispatch Gumball and choose one of the gumballs that can perform the search. There are currently 5 gumballs that can be chosen and there doesn't seem to be any reason to ever pick another gumball than the fastest searcher that you own.

You cannot search Eternal Volcano if there is an ongoing search on Tartarus Gate and vice-versa.

Search gumballs:

With Fire Giant, the search takes 10 hours and can be speed up for 10 Gem

Possible rewards:

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