Oasis Wall-mounted Fountain

Taken all the way down to base materials, one Oasis Wall-mounted Fountain is 3 crafting steps deep and needs 3 intermediates — Hard Mudstone Whetstone ×2, Mortar ×2 and Distilled Water ×2 — which resolve to 6 distinct raw materials totalling 18 units, plus 30 crystals.

That bill outweighs 7,380 of the 13,602 recipes tracked here and 694 of the 1,441 Armorer ones, and 337 recipes nest deeper.

Only 14 of those crystals go into the final step; the other 16 are burned by the intermediates, so the real crystal cost is 12 Wind Crystal, 7 Earth Crystal, 7 Ice Crystal and 1 other kind.

The chain crosses three disciplines — Armorer to Lv 80, Goldsmith to Lv 71 and Alchemist to Lv 20 — so no single class can finish it unaided.

All 6 raw materials are gathered, and not one of their spots is timed, so nothing in the tree waits on the Eorzean clock.

Of the intermediates, Mortar has the widest use: 140 recipes call for it, spanning six of the eight crafting classes.