Inferno Axe

Taken all the way down to base materials, one Inferno Axe is 3 crafting steps deep and needs 4 intermediates — Brass Ingot ×1, Iron War Axe ×1, Iron Ingot ×3 and 1 other — which resolve to 4 distinct raw materials totalling 15 units, plus 10 crystals.

That bill outweighs 6,735 of the 13,602 recipes tracked here and 730 of the 1,932 Blacksmith ones, and 337 recipes nest deeper.

Only 3 of those crystals go into the final step; the other 7 are burned by the intermediates, so the real crystal cost is 6 Fire Shard, 2 Earth Shard and 2 Wind Shard.

The chain crosses three disciplines — Blacksmith to Lv 21, Goldsmith to Lv 14 and Carpenter to Lv 10 — so no single class can finish it unaided.

All 4 raw materials are gathered, and not one of their spots is timed, so nothing in the tree waits on the Eorzean clock.

Inferno Axe is itself consumed by 1 further recipe, all of them Blacksmith recipes.