Shoot First, Loot Later

Before collecting any treasures, visit the Vindicaar Matrix Core in the basement of the Vindicaar ship to unlock Light's Judgment, Lightforged Warframe, and Shroud of Arcane Echoes — you can only have one active at a time and must switch between them as needed. These abilities are found in your spellbook, not as an extra action button.

There are five hidden treasures in Krokuun: find the Krokul Emergency Cache at 51.3, 76.2 (enter through rocks at 50.69, 75.33 destroyed with Lightforged Warframe), the Lost Krokul Chest at 48.5, 58.9 (enter through rocks at 47.81, 59.25 destroyed with Light's Judgment), the Legion Tower Chest at 62.8, 37.6 (enter through rocks at 64.09, 39.06 destroyed with Light's Judgment), the Long-Lost Augari Treasure at 75.1, 69.8 (requires Shroud of Arcane Echoes), and Precious Augari Keepsakes at 55.9, 74.1 (requires Shroud of Arcane Echoes). Note that chests marked on the minimap do not count toward this achievement — only these hidden ones do.

Collect the following hidden treasures in Eredath: Chest of Ill-Gotten Gains at 50.6, 38.4 (Light's Judgment), Void-Tinged Chest at 40.2, 51.4 (Lightforged Warframe), Augari-Runed Chest at 70.6, 27.3, Secret Augari Chest at 62.2, 22.4, Augari Goods at 40.8, 69.8, a chest at 62.2, 71.2, and Eredar Treasure Cache at 42.9, 5.5 (start on the ledge at 44.53, 5.66 and use Lightforged Warframe to destroy the rocks).

Collect the following hidden treasures in Antoran Wastes: Ancient Legion War Cache at 65.9, 39.8, Fel-Bound Chest at 52.1, 27.2 (Light's Judgment), Timeworn Fel Chest at 75.7, 52.6, Legion Treasure Hoard at 49, 59.3, Forgotten Legion Supplies at 58.9, 61.4 (Lightforged Warframe), and Missing Augari Chest at 57.4, 63.6 (Shroud of Arcane Echoes).