How to solve the Moonstone Pillars Merlin Trials in Hogwarts Legacy
Solving the Moonstone Pillars Merlin Trials in Hogwarts Legacy might seem complex, but it only requires a simple spell.
Ethan Webb 
Screenshot by Gamepur
Unlike the Arithmancy Door Puzzles found in the academy of Hogwarts Legacy, the Merlin Trials are varied in their solutions and involve different approaches to be solved with magic, such as the trial with Moonstone Pillars. Those who have unlocked the Room of Requirement will recognize Moonstone as the primary resource used to conjure utility workstations, decorations, and structures for Beast care. In the case of this particular Merlin Trial, you will find gem clusters of Moonstones in three obelisks near the puzzle’s central stone plate. Accordingly, to solve this puzzle, you will need to activate these pillars to complete the trial.
Related: How to open Arithmancy doors in Hogwarts Legacy
Moonstone Pillars Merlin Trial Solution in Hogwarts Legacy
At first, the Moonstone Pillars Merlin Trial in Hogwarts Legacy might seem more complicated than it actually is, as the Moonstone crystals inside each obelisk’s hollow cannot be destroyed or interacted with like in the open world. Luckily, the puzzle is notably straightforward to solve and only requires the early-game Spell Lumos. If you glance around the nearby area of a Moonstone Pillars Merlin Trial, you will notice multiple eclipses of glowing moths hovering about distinct locations. These magical moths are the key to activating the Merlin Trial.
Similar to how you used Lumos to guide Moths to their frames for the Moth Mirror puzzles in Hogwarts Legacy, you must use the light of your Wand to direct the glowing moth eclipses to the three obelisks in the Moonstone Pillars Merlin Trial. For clarification, walk up to the eclipse, cast Lumos, and walk to any one of the three columns with Moonstone. Repeat this process two more times to clear the trial and receive your XP reward and Challenge progression.
While every Moonstone Pillars Merlin Trial in Hogwarts Legacy is solved using the same method described above, not every trial will have the same topographical layout. For example, the first Moonstone Pillar trial you might have encountered is on the hill north of the main road where you accompany Sebastian or Natsai to Hogsmeade. All the glowing moths for the puzzle are easy to find.
On the other hand, a Moonstone Pillars Merlin Trial near the Forbidden Forest’s Hippogriff Den is guarded by hostile Poachers. Furthermore, you will need to use Incendio and Depulso to clear away obstacles to reach the moths. In such trials, using Revelio to locate objects of interest is essential to solving the puzzle.