Adamantite Uchigatana

Taken all the way down to base materials, one Adamantite Uchigatana is 4 crafting steps deep and needs 10 intermediates — Adamantite Nugget ×3, Cloud Mica Whetstone ×1, Electrum Ingot ×1 and 7 others — which resolve to 9 distinct raw materials totalling 45 units, plus 65 crystals.

That bill outweighs 12,451 of the 13,602 recipes tracked here and 1,645 of the 1,932 Blacksmith ones, and 1 recipe nests deeper.

Only 10 of those crystals go into the final step; the other 55 are burned by the intermediates, so the real crystal cost is 20 Fire Crystal, 14 Wind Crystal, 10 Water Crystal and 4 other kinds.

The chain crosses five disciplines — Blacksmith to Lv 58, Alchemist to Lv 56, Carpenter to Lv 56, Goldsmith to Lv 56 and Weaver to Lv 56 — so no single class can finish it unaided.

All 9 raw materials are gathered, and 3 of them are time-gated: Adamantite Ore (0:00, 2:00, 6:00, 10:00, 12:00, 14:00, 18:00, 22:00), Abalathian Mistletoe (6:00, 18:00) and 1 other. The widest gap between consecutive opening times is 4 Eorzean hours, about 12 real-world minutes.

Of the intermediates, Electrum Ingot has the widest use: 234 recipes call for it, spanning seven of the eight crafting classes.