Tier 4 Metal Aquarium ★★

Taken all the way down to base materials, one Tier 4 Metal Aquarium is 3 crafting steps deep and needs 5 intermediates — Chromite Ingot ×6, Wolfram Ingot ×4, Crystal Glass ×1 and 2 others — which resolve to 12 distinct raw materials totalling 99 units, plus 87 crystals.

That bill outweighs 13,468 of the 13,602 recipes tracked here and 1,424 of the 1,441 Armorer ones, and 337 recipes nest deeper.

Only 14 of those crystals go into the final step; the other 73 are burned by the intermediates, so the real crystal cost is 30 Fire Crystal, 20 Fire Cluster, 16 Earth Cluster and 4 other kinds.

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

9 of the 12 raw materials come out of the ground, and 2 of them are time-gated: Chromite Ore (10:00, 22:00) and Ferberite (3:00). The widest gap between consecutive opening times is 12 Eorzean hours, about 35 real-world minutes.

Of the intermediates, Chromite Ingot has the widest use: 121 recipes call for it, spanning six of the eight crafting classes.