Few side quests in Hogwarts Legacy introduce a new gameplay mechanic as smoothly as The Lost Astrolabe. By 2026, with the game still thriving thanks to consistent updates and a dedicated community, every new witch or wizard should prioritize this early adventure. It not only showers you with a charming cosmetic reward but also unlocks the ability to dive—a feature that opens up whole underwater sections of the Black Lake throughout the Highlands.
The quest-giver is Grace Pinch-Smedley, a Slytherin student who can be found on the docks of Lower Hogsfield, a quaint hamlet in the South Hogwarts Region. A word of caution, however: Lower Hogsfield is home to level‑20‑ish Cottongrass Dugbogs and Ashwinder scouts, so it is wise to push the story forward until Natty accompanies you there. Once you have visited Hogsmeade with either companion, Natty’s quest to Lower Hogsfield becomes available. By then your character should be at least Level 7, equipped with a few upgraded spells like Incendio or Confringo to handle any unexpected swamp beast.
🏞️ Locating Grace and Starting the Quest
You can reach Lower Hogsfield instantly by using any nearby Floo Flame. After teleporting, head straight to the wooden pier extending into the Black Lake. Grace stands at the end, fretting over a family heirloom that has tumbled into the water. Speak to her, and she will explain that an antique astrolabe — a celestial navigation instrument belonging to the Pinch-Smedley line — lies somewhere in the lake’s murky depths.
Grace doesn’t give you an exact spot; instead, she points to shimmering bubble clusters on the surface. These are diving points, a new interaction you will use over and over again. The moment the quest begins, the lake area becomes dotted with glistening, swirling patches of water. That’s your cue.
🌊 Diving Down to the Astrolabe
Once you wade or swim towards a bubbling patch, a prompt appears to dive. Press the action button and your character will plunge beneath the surface, bringing you into a brief underwater exploration sequence. Here’s what you need to know:
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🔍 Bubble Clusters: Each cluster represents a possible hiding place. The astrolabe is always in one of them, but you might dig up a Wiggenweld Potion or a random gear piece first.
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🐊 Cottongrass Dugbogs: These large, crocodilian beasts patrol the shallow water near the diving spots. You can either sneak past them or engage. Every Dugbog defeat yields a Dugbog Tongue, an ingredient essential for brewing the Focus Potion later in the game.
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⏱️ Oxygen Gauge: A small bar depletes while underwater. You have ample time to search, but don’t dawdle.
Players often ask whether they should clear out the Dugbogs before diving. The answer is a resounding yes — if only to stockpile tongues. Focus Potion reduces spell cooldowns significantly, making it a staple in hard‑mode combat. Collecting tongues early saves you from grinding the same beasts later.
🪄 Step‑by‑Step Search Method
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Fast‑travel to Lower Hogsfield Floo Flame.
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Walk down to the pier and start the conversation with Grace.
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Summon your broom if you like, or simply swim to the first bubble patch.
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Dive and inspect the glowing object.
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Repeat at other bubble patches until the game announces you’ve found the astrolabe.
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Return to Grace on the dock.
The entire process rarely takes more than five minutes, even if you tackle a Dugbog or two. The bubbles are clustered tightly together, so you won’t need to explore the entire lake. If you’re having trouble spotting them, cast Revelio on land — the diving points will emit a soft golden sparkle.
🎁 Rewards and the Big Decision
Once you hand over the antique astrolabe, Grace offers you a choice: return it free of charge, demand extra payment, or keep the heirloom for yourself. Regardless of your moral alignment, the base rewards are identical. You receive:
| Reward | Details |
|---|---|
| Experience Points | 180 XP |
| Mermaid Mask | Unique facewear cosmetic (transmog available) |
| Miscellaneous Loot | Any Wiggenweld Potions, gear items, and beast parts salvaged during the dive |
The Mermaid Mask is a whimsical piece, covering the upper half of your face in silvery scales with a delicate pearl at the center. It pairs beautifully with the diving‑themed attire you’ll find later in the game. More importantly, keeping the mask in your inventory unlocks the appearance permanently in the gear transmogrification menu.
But the real prize of this quest is diving itself. After The Lost Astrolabe, you can revisit any body of water marked with bubbles across the Highlands and dive for chests, ingredients, and even hidden quest items. Many treasure vaults and late‑game puzzles rely on this mechanic, so completing the quest early is a massive quality‑of‑life upgrade.
🌿 A Handy Tip for Potion Brewers
If you snagged a few Dugbog Tongues during the quest, hold onto them. The Focus Potion recipe – unlocked through main story progression – calls for one Fluxweed Stem, one Lacewing Fly, and one Dugbog Tongue. Having a dozen tongues in your stash by the time the recipe is available will save you from backtracking to Lower Hogsfield at a later hour.
Even in 2026, when builds and strategies have been refined to an art, the smooth integration of side quests like The Lost Astrolabe stands out. Grace Pinch-Smedley’s little errand may seem trivial, but it quietly teaches new players how to swim, dive, and manage threats—all while dropping a charming memento for their first field guide page.