Nightsteel File ★★★

Taken all the way down to base materials, one Nightsteel File is 4 crafting steps deep and needs 6 intermediates — Nightsteel Ingot ×4, Hawk's Eye Sand ×3, Ground Sloth Leather ×2 and 3 others — which resolve to 14 distinct raw materials totalling 59 units, plus 43 crystals.

That bill outweighs 13,079 of the 13,602 recipes tracked here and 1,790 of the 1,932 Blacksmith ones, and 1 recipe nests deeper.

Only 4 of those crystals go into the final step; the other 39 are burned by the intermediates, so the real crystal cost is 12 Fire Crystal, 8 Earth Cluster, 7 Fire Cluster and 3 other kinds.

The chain crosses four disciplines — Blacksmith to Lv 70, Alchemist to Lv 70, Leatherworker to Lv 70 and Goldsmith to Lv 50 — so no single class can finish it unaided.

7 of the 14 raw materials come out of the ground, and 4 of them are time-gated: Hawk's Eye (6:00, 18:00), Nightsteel Ore (6:00, 18:00) and 2 others. The widest gap between consecutive opening times is 10 Eorzean hours, about 29 real-world minutes.

Of the intermediates, Gold Ingot has the widest use: 184 recipes call for it, spanning seven of the eight crafting classes.