Mysterious Cave sits on the western shoreline, reachable by following the coast down from the Ministry of Accuracy. The entrance is carved into the rock near the waterline, with mineral growths outside that you can harvest along the way. Expect hostile wildlife in the area.

Start Inez’s “Better Than Nature” (required to use the Phonotron)

Before the cave matters, you need Inez’s companion quest, Better Than Nature. Speak with Ethel Tinsley on the outskirts of Fairfield to begin it. She directs you to two potential graft donors for Inez, including a Skeleton Crabble found at Mysterious Cave. With the quest active, you’ll be able to authorize the machinery inside the cave.

Activate the Phonotron to summon the Skeleton Crabble

Inside, Inez will walk to an array of research equipment and ask you to activate the Phonotron. This device is the trigger for the encounter: once powered, it lures a Skeleton Crabble up through the raised section of the cavern floor. Without the companion quest in progress, the controls won’t engage.

Combat: Skeleton Crabble, Bulletclaws, and Hammerclaws

The Skeleton Crabble hits hard and doesn’t arrive alone. Smaller Crabbles—Bulletclaws and Hammerclaws—join the fight and will swarm if you stay in place. Keep moving, use crowd control liberally, and concentrate damage on the Skeleton Crabble to end the encounter faster.

  • Focus fire: burn down the Skeleton Crabble as your primary target.
  • Thin the pack: stagger or disable Bulletclaws/Hammerclaws when they cluster.
  • Leverage companions: time abilities to interrupt the Crabble’s big swings.

Loot and quest turn‑in

Loot the Skeleton Crabble Grafting Specimen from the large Crabble’s corpse. Return it to Tinsley in Fairfield to proceed with Inez’s graft. Choosing the Crabble graft unlocks Inez’s The Magic Bullet ability, which fires a volley of hot plasma at a target.

Optional interactions and skill checks inside the cave

  • Skill checks: a makeshift worktable allows “Recover Undetonated Mines” with Explosives 4; a report titled “A Study in Sound” can be parsed with Science 4.
  • Environmental story: logs labeled “Confirmed Skeleton Crabble Sighting” and “Free Salvage, Brought to you by Auntie’s Choice” are found on consoles and tables.
  • Notable corpse: Trooper Connelly carries a Mag‑Pick you can loot.
  • Resource node: Ferrochromium can be found outside the cave entrance.

Items you can pick up in Mysterious Cave

Category Item Quantity/Notes
Thrown ItemsExplosive Grenadex3
ConsumablesAuntie Fizzo's Citrus‑Related Beveragex2
ConsumablesBoarst Rocketsx1
ConsumablesBoarst Wurstx2
ConsumablesDeep Fried Crysty‑Bitsx1
ConsumablesEarl’s Grey Teax1
Consumables/ToolMag‑Pickx1 (also on Trooper Connelly)
ConsumablesSnack Cakesx1
Inhalers & GadgetsAuntie‑Biotics Cremex1
ResourcesBit Cartridge—
ResourcesBlack Powderx1
ResourcesClothx6
ResourcesCrabble Plasma Glandx1
ResourcesCrude Biomassx5
ResourcesEnergy Canisterx2
ResourcesScrap Metalx2
Quest ItemSkeleton Crabble Grafting SpecimenDropped by Skeleton Crabble
JunkArboreal Screamer Hide—
JunkCandid Skull Fin—
JunkCigarette Lighter—
JunkCrabble Meat—

XP and small notes

  • Discovering Mysterious Cave grants +100 XP.
  • The Phonotron console becomes usable only after starting Inez’s companion quest.
  • If you’re pursuing access to the Vox Relay as part of Inez’s objectives, Tinsley also points you toward a separate Raptidon Matriarch target elsewhere on the island.

Once the Skeleton Crabble is dealt with and the specimen secured, the location’s main purpose is complete. If you opted for the graft, test The Magic Bullet in your next encounter—its plasma volley gives Inez a clear spike in burst damage.