FFXVI Darksteel - Where to get, uses, etc

Darksteel is a crafting material used in the endgame. Here we talk how and where to get Darksteel.

Darksteel - How and Where to get it?

Hunt (Usher to the Underworld) Thanatos: A Rank, very close to the endgame.

Hunt (The Grim Reaper) Prince of Death: S Rank, one of the final hunts.

Both of these hunts are very close to the endgame. No sidequests seem to reward Darksteel, or Main Scenario ones either.

I don't think there are other sources, but you will have exactly how many you need after these two.

Darksteel - Uses

Darksteel is (only?) used to make the best "non-NG+" "non-FFmode" weapon, Gotterdammerung.

These Mini Guides are meant to answer very specific questions succintly. You might also be interested in:
FFXVI Walkthrough (SPOILER FREE) | All FFXVI Hunts | All FFXVI Sidequests List