Dwarven Mythril Needle

Taken all the way down to base materials, one Dwarven Mythril Needle is 2 crafting steps deep and needs 4 intermediates — Dwarven Mythril Nugget ×2, Dwarven Mythril Ingot ×1, Lignum Vitae Lumber ×1 and 1 other — which resolve to 6 distinct raw materials totalling 22 units, plus 49 crystals.

That bill outweighs 8,402 of the 13,602 recipes tracked here and 1,234 of the 2,216 Goldsmith ones, and 4,464 recipes nest deeper.

Only 14 of those crystals go into the final step; the other 35 are burned by the intermediates, so the real crystal cost is 35 Wind Crystal and 14 Fire Crystal.

The chain crosses three disciplines — Goldsmith to Lv 80, Blacksmith to Lv 78 and Carpenter to Lv 78 — 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, Dwarven Mythril Ingot has the widest use: 168 recipes call for it, spanning seven of the eight crafting classes.