Skull Cavern

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Skull Cavern Entrance
For ladder/shaft spawn rates, special monster drops, and the contents of crates and barrels, see The Mines.

The Skull Cavern is located in the northwest area of the Desert. It is initially locked and requires the Skull Key to gain access.


A shaft for faster descending

There is no practical limit to the number of floors (sometimes called levels) in the Skull Cavern.[1] Similar to the Mines, the Player advances through floors in the Skull Cavern by finding a ladder on each floor, either by mining rocks or defeating enemies. The Skull Cavern has the same possible floor layouts as the ones in the Mines.

Unlike the Mines, there is no elevator to save progress, but on every floor there is a ladder at the starting point where the Player can leave the Skull Cavern. Each visit must start again from the first floor.

When ladders to the next floor appear from breaking rocks, 20% of the time they will appear as a shaft (or hole) instead of a ladder. Shafts make it possible to travel 3-15 floors at a time. The number of floors dropped is based on an integer x between 3 and 8 inclusive, chosen with equal probability, with a 90% chance that the player drops x floors and a 10% chance that the player drops 2x-1 floors. The amount of floors dropped is predetermined based on the mine floor, game day, and Random Seed. In particular, Luck does not affect the chances of jumping down a certain number of floors. This also means that if multiple shafts spawn on the same floor, they will all drop the player the same number of floors, so it does not matter which one is chosen. Jumping down the shaft causes Health damage equal to 3x the number of floors skipped (although jumping down a shaft will never reduce health to less than 1). Note that if a shaft above floor 100 is calculated to drop the player past floor 100, it will be modified to only drop the player to floor 100.[2]

If the player runs out of health while exploring Skull Cavern, they will wake up sometime later on the same day in Harvey's Clinic. A fee of data-sort-value="1000">Gold.png1,000g will be deducted for emergency surgery. Several items may also be lost. Passing out at 2:00 am will cause the player to lose data-sort-value="1000">Gold.png1,000g or 10% of funds, whichever is less.


The chance to find Iridium Ore increases slowly and steadily as the player descends into the Skull Cavern, rapidly increasing from floor 10 to 100. See Skull Cavern/Ore Distribution for more details.

The monsters in the Skull Cavern also have a chance to drop Iridium Ore and Iridium Bars, as well as special items. It can be a good idea to bring the Lava Katana or Galaxy Sword, as enemies are particularly strong.

High Luck increases the frequency of ladders/shafts. Rapid descent to floors with a higher chance of spawning Iridium Nodes is often more efficient for acquiring ore than thorough exploration. Staircases can also be stacked, so a single inventory slot can hold 999 staircases. Even blindly placing staircases will take some time though; the lower the player descends with staircases, the less time they have to explore the Skull Cavern.

Qi's Challenge

After entering the Cavern for the first time, a letter will be received on the following day from Mr. Qi. The letter begins the quest Qi's Challenge, which is completed by reaching floor 25 in the Skull Cavern. Completing the quest awards data-sort-value="10000">Gold.png10,000g, delivered by mail the following day. If the player reaches floor 25 of the Skull Cavern during the first visit, the quest will automatically be fulfilled the next day.

Qi's Hungry Challenge

"Qi's Hungry Challenge" is a possible, repeatable Special Order, that may be accepted in Qi's Walnut Room on Ginger Island. It is completed by reaching floor 100 of the Skull Cavern within the given time limit. While this quest is active, no food or drink items can be consumed while the player is in the Skull Cavern. Buffs from food/drink before entering the Skull Cavern will stay active.

While this quest is active, Big Slimes may occasionally have hearts that will give 10 health points when slain. Another strategy to regain health without eating is to equip one or more Vampire Rings or to use a weapon with the Vampiric enchantment.

The use of staircases is permitted. Completing the quest awards data-sort-value="25">Qi Gem.png 25 Qi Gems.

Skull Cavern Invasion

The "Skull Cavern Invasion" is a possible, repeatable Special Order, that may be accepted in Qi's Walnut Room on Ginger Island. It is completed by reaching floor 100 of the Skull Cavern within the given time limit. While the quest is active, stronger variations of monsters occupy the Cavern; similarly to the Dangerous Mines. Radioactive Nodes can also spawn here, like the Dangerous Mines.

The use of staircases is permitted. Completing the quest awards data-sort-value="40">Qi Gem.png 40 Qi Gems. After completing the challenge for the first time, the statue at the Cavern's entrance can be used to toggle hard mode in the cavern.


Time runs more slowly in Skull Cavern than elsewhere in the game: whereas one hour of game time normally lasts 43 seconds, in Skull Cavern one hour lasts 54 seconds (25% longer). However, time reverts to normal 43-second hours in multiplayer games and on Prehistoric Floors.[3]

This has two main implications:

  • Players have more real-time available before the end of the day, and should be able to descend deeper than otherwise.
  • The game-time duration of any buff is decreased.

This adjustment in timing has no effect upon other aspects of the game, such as equipment processing times. For example, Honey placed in a Keg at noon is ready with Mead at 10 pm even if the player spends most of that time in the Skull Cavern.



Shown below are foods with Buffs that are useful when exploring the Skull Cavern. Note that eating a food with buffs will wipe out any active buffs and replace them with the buffs from the newly eaten food. If the newly eaten food has no buffs, the existing buffs will remain in effect. Coffee, Triple Shot Espresso and Ginger Ale are an exception to this rule; they will stack with other food buffs (but not each other).

Image Name Ingredients Energy / Health Buff(s) Duration
Autumn's Bounty.png
Autumn's Bounty Yam.png Yam (1)Pumpkin.png Pumpkin (1) Energy.png220Health.png99 Foraging.png Foraging (+2)Defense.png Defense (+2) Time Icon.png 7m 41s
Coffee Coffee Bean.png Coffee Bean (5) Energy.png3Health.png1 Speed.png Speed (+1) Time Icon.png 1m 23s
Crab Cakes.png
Crab Cakes Crab.png Crab (1)Wheat Flour.png Wheat Flour (1)Egg.png Egg (1)Oil.png Oil (1) Energy.png225Health.png101 Speed.png Speed (+1)Defense.png Defense (+1) Time Icon.png 16m 47s
Cranberry Sauce.png
Cranberry Sauce Cranberries.png Cranberries (1)Sugar.png Sugar (1) Energy.png125Health.png56 Mining.png Mining (+2) Time Icon.png 3m 30s
Eggplant Parmesan.png
Eggplant Parmesan Eggplant.png Eggplant (1)Tomato.png Tomato (1) Energy.png175Health.png78 Mining.png Mining (+1)Defense.png Defense (+3) Time Icon.png 4m 39s
Fried Eel.png
Fried Eel Eel.png Eel (1)Oil.png Oil (1) Energy.png75Health.png33 Luck.png Luck (+1) Time Icon.png 7m
Fried Mushroom.png
Fried Mushroom Common Mushroom.png Common Mushroom (1)Morel.png Morel (1)Oil.png Oil (1) Energy.png135Health.png60 Attack.png Attack (+2) Time Icon.png 7m
Ginger Ale.png
Ginger Ale Ginger.png Ginger (3)Sugar.png Sugar (1) Energy.png63Health.png28 Luck.png Luck (+1) Time Icon.png 5m
Lucky Lunch.png
Lucky Lunch Sea Cucumber.png Sea Cucumber (1)Tortilla.png Tortilla (1)Blue Jazz.png Blue Jazz (1) Energy.png100Health.png45 Luck.png Luck (+3) Time Icon.png 11m 11s
Magic Rock Candy.png
Magic Rock Candy N/A Energy.png500Health.png225 Mining.png Mining (+2)Luck.png Luck (+5)Speed.png Speed (+1)Defense.png Defense (+5)Attack.png Attack (+5) Time Icon.png 8m 24s
Maple Bar.png
Maple Bar Maple Syrup.png Maple Syrup (1)Sugar.png Sugar (1)Wheat Flour.png Wheat Flour (1) Energy.png225Health.png101 Farming.png Farming (+1)Fishing.png Fishing (+1)Mining.png Mining (+1) Time Icon.png 16m 47s
Miner's Treat.png
Miner's Treat Cave Carrot.png Cave Carrot (2)Sugar.png Sugar (1)Milk.png Milk (1) Energy.png125Health.png56 Mining.png Mining (+3)Magnetism.png Magnetism (+32) Time Icon.png 5m 35s
Pepper Poppers.png
Pepper Poppers Hot Pepper.png Hot Pepper (1)Cheese.png Cheese (1) Energy.png130Health.png58 Speed.png Speed (+1)Farming.png Farming (+2) Time Icon.png 7m
Pumpkin Soup.png
Pumpkin Soup Pumpkin.png Pumpkin (1)Milk.png Milk (1) Energy.png200Health.png90 Luck.png Luck (+2)Defense.png Defense (+2) Time Icon.png 7m 41s
Roots Platter.png
Roots Platter Cave Carrot.png Cave Carrot (1)Winter Root.png Winter Root (1) Energy.png125Health.png56 Attack.png Attack (+3) Time Icon.png 5m 35s
Spicy Eel.png
Spicy Eel Eel.png Eel (1)Hot Pepper.png Hot Pepper (1) Energy.png115Health.png51 Luck.png Luck (+1)Speed.png Speed (+1) Time Icon.png 7m
Stuffing Bread.png Bread (1)Cranberries.png Cranberries (1)Hazelnut.png Hazelnut (1) Energy.png170Health.png76 Defense.png Defense (+2) Time Icon.png 5m 35s
Super Meal.png
Super Meal Bok Choy.png Bok Choy (1)Cranberries.png Cranberries (1)Artichoke.png Artichoke (1) Energy.png160Health.png72 Speed.png Speed (+1)Max Energy.png Max Energy (+40) Time Icon.png 3m 30s
Triple Shot Espresso.png
Triple Shot Espresso Coffee.png Coffee (3) Energy.png8Health.png3 Speed.png Speed (+1) Time Icon.png 4m 12s


Bombs make quick work of densely-clustered stones and ore veins. They can also be used for permanently defeating Mummies.

Bombs can be crafted, or purchased from Dwarf:

Image Name Ingredients Purchase Price
Cherry Bomb.png
Cherry Bomb Copper Ore.png Copper Ore (4)Coal.png Coal (1) data-sort-value="300">Gold.png300g
Bomb Iron Ore.png Iron Ore (4)Coal.png Coal (1) data-sort-value="1000">Gold.png1,000g
Mega Bomb.png
Mega Bomb Gold Ore.png Gold Ore (4)Solar Essence.png Solar Essence (1)Void Essence.png Void Essence (1) data-sort-value="1600">Gold.png1,600g

The Slingshot's Explosive Ammo is also effective in dealing with small groups of stones, Iridium Ore deposits, and incapacitated Mummies. Loading the Slingshot with Gold Ore deals substantial damage, making it potentially useful for dispatching tough targets. Explosive ammo can be crafted, or bought at the Adventurer's Guild for data-sort-value="300">Gold.png300g.


Staircases can be used for rapid descent or skipping troublesome floors. If the player has one or more Crystalariums, they can be used to produce Jade which can be traded for Staircases with the Desert Trader on Sundays.


Several Rings may assist in exploring the Skull Cavern. See the Rings page for full descriptions.

Warp Totems

A Warp Totem can be used to make a quick exit if supplies are running low or the day is almost over to avoid the fee of up to data-sort-value="1000">Gold.png1,000g for passing out at 2:00 am.

A Warp Totem: Desert (or Desert Obelisk) can be used to access the Desert about 4 hours earlier than Pam arrives at the Bus Stop.


Image Monster HP Damage Notes
Armored Bug.png
Armored Bug 1 8 Can only be killed while using a weapon with the bug killer enchantment.
Big Purple Slime.png
Big Slime 60 5 A chance to split into smaller Slimes when killed. Big Slimes are purple in the Skull Cavern.
Purple Slime.png
Purple Slime 410 28 Can drop Iridium Ore and Iridium Bars.
Lava Bat.png
Lava Bat 80 15 Only appears on floors 20 and 40 unless 20 or 40 are mummy floors; flies.
Mummy 260 30 Appears on Mummy floors. Needs to be finished with a bomb of any type after being knocked out with other weapons. If a bomb does enough damage to knock the Mummy out, it will also destroy it. Using a weapon with the Crusader enchantment stops them from reviving. Frequently drops Solar Essence when slain, and occasionally drops Cloth.
Serpent 150 23 Moves quickly; default flying enemy. Frequently drops Void Essence. Occasionally drops Spicy Eel and Bombs.
Iridium Bat.png
Iridium Bat 300 30 Appears at floor 51+ and on prehistoric floors. Very high HP and Damage. Frequently drops Iridium Ore and Solar Essence.
Iridium Crab.png
Iridium Crab 240 15 Appears at floor 26+ except not on mummy floors. Can drop Iridium Ore and Crab Cakes.
Carbon Ghost.png
Carbon Ghost 190 25 Can appear on Mummy floors. Frequently drop Omni Geodes. May occasionally drop Refined Quartz.
Pepper Rex.png
Pepper Rex 300 15 Appears mainly on prehistoric floors; breathes fire. Drops Dinosaur Egg or one of 3 prehistoric Artifacts.
Mutant Fly.png
Mutant Fly 66 12 Can appear on prehistoric floors.
Armored Bug Dangerous.png
Armored Bug (dangerous) 250 20-27 Only appears when the Skull Cavern is in a "dangerous" state.
Mummy Dangerous.png
Mummy (dangerous) 445 38-55 Only appears when the Skull Cavern is in a "dangerous" state.
Royal Serpent.png
Royal Serpent 300-1050 32-48 Only appears when the Skull Cavern is in a "dangerous" state.
Purple Slime Dangerous.png
Purple Slime (dangerous) 403 20-30 Only appears when the Skull Cavern is in a "dangerous" state.

Prehistoric Floors

See also: The Mines#Infested Floors
A Prehistoric Floor

Prehistoric floors are a type of infested floor containing mainly Pepper Rex monsters. Mutant Flies and Iridium Bats can also spawn and attack the player there. Dinosaur Eggs and Fiddlehead Ferns can be foraged on Prehistoric floors. Foliage on this floor has a chance to yield an Ancient Seed when cut down. There is a ~2.2% chance to encounter a prehistoric floor at and below floor 7.[4]

Because prehistoric floors are infested, all enemies on this floor must be killed before a ladder appears.

Treasure Rooms

Rotten Plant.png  Warning: Spoilers  Rotten Plant 2.png

This page or section contains unmarked spoilers from update 1.6 of Stardew Valley. Players may want to avoid or be cautious toward reading this article/section.

Small rooms containing treasure chests, similar to those in the Mines, can randomly appear at floors 10+. Daily luck and luck buffs affect the chance to find Treasure Rooms.

The probability of encountering one when entering a new floor equals to 0.01 + (Daily Luck / 10) + (Luck Buffs / 100).[4] This means Treasure Rooms have a base chance of 1% to appear with daily luck increasing the chance by 1% at best or decreasing by 1% at worst, with the Special Charm adding 0.25%, and food buffs adding 1% for every point of luck. In multiplayer, the luck values taken into account are the average of luck stats of players present in the Skull Cavern.

Floor 100 of the Skull Cavern is guaranteed to contain a treasure chest. The only exception is during the run where the player completes the secret. Floors 200 and 300 of the Skull Cavern are also guaranteed to contain 2 and 3 treasure chests, respectively.

Below is a table of all possible treasures that can be randomly found inside Treasure Chests in the Skull Cavern. All percent chances listed below are assuming that the player has claimed Farming Mastery (for the Golden Animal Cracker) and Combat Mastery (for the Trinkets). If either or both have not been claimed, then the chances for all other available items are slightly increased.

Image Name Quantity  Chance [5] 
Golden Animal Cracker.png
Golden Animal Cracker 1 2%
Basilisk Paw.png
Basilisk Paw 1 0.63%
Fairy Box.png
Fairy Box 1 0.63%
Green Frog Egg.png
Frog Egg 1 0.63%
Golden Spur.png
Golden Spur 1 0.63%
Ice Rod.png
Ice Rod 1 0.63%
Magic Quiver.png
Magic Quiver 1 0.63%
Parrot Egg.png
Parrot Egg 1 0.63%
Mega Bomb.png
Mega Bomb 5 3.6%
Bomb 10 3.6%
Artifact Trove.png
Artifact Trove 5 1.22% (if Volcano Shortcut is open)
3.6% (if Volcano Shortcut isn't open)[6]
Cinder Shard.png
Cinder Shard 10-20 2.38% (if Volcano Shortcut is open)
0% (if Volcano Shortcut isn't open)[6]
Life Elixir.png
Life Elixir 2-4 3.6%
Omni Geode.png
Omni Geode 5 2.7% (if Mystery Boxes are available)
5.4% (if Mystery Boxes aren't available)[7]
Omni Geode.png
Omni Geode 10 0.9% (if Mystery Boxes are available)
1.8% (if Mystery Boxes aren't available)[7]
Warp Totem Farm.png
Warp Totem: Farm 5 3.6%
Rain Totem.png
Rain Totem 1-3 3.6%
Cherry Sapling.png
Cherry Sapling 1 0.6%
Apricot Sapling.png
Apricot Sapling 1 0.6%
Orange Sapling.png
Orange Sapling 1 0.6%
Peach Sapling.png
Peach Sapling 1 0.6%
Pomegranate Sapling.png
Pomegranate Sapling 1 0.6%
Apple Sapling.png
Apple Sapling 1 0.6%
Iridium Sprinkler.png
Iridium Sprinkler 1-2 3.6%
Quality Sprinkler.png
Quality Sprinkler 4 3.6%
Parsnip Seeds.png
Parsnip Seeds 5-20 0.09%
Bean Starter.png
Bean Starter 5-20 0.09%
Cauliflower Seeds.png
Cauliflower Seeds 5-20 0.09%
Potato Seeds.png
Potato Seeds 5-20 0.09%
Garlic Seeds.png
Garlic Seeds 5-20 0.09%
Kale Seeds.png
Kale Seeds 5-20 0.09%
Rhubarb Seeds.png
Rhubarb Seeds 5-20 0.09%
Melon Seeds.png
Melon Seeds 5-20 0.09%
Tomato Seeds.png
Tomato Seeds 5-20 0.09%
Blueberry Seeds.png
Blueberry Seeds 5-20 0.09%
Pepper Seeds.png
Pepper Seeds 5-20 0.09%
Wheat Seeds.png
Wheat Seeds 5-20 0.09%
Radish Seeds.png
Radish Seeds 5-20 0.09%
Red Cabbage Seeds.png
Red Cabbage Seeds 5-20 0.09%
Starfruit Seeds.png
Starfruit Seeds 5-20 0.09%
Corn Seeds.png
Corn Seeds 5-20 0.09%
Eggplant Seeds.png
Eggplant Seeds 5-20 0.09%
Artichoke Seeds.png
Artichoke Seeds 5-20 0.09%
Pumpkin Seeds.png
Pumpkin Seeds 5-20 0.09%
Bok Choy Seeds.png
Bok Choy Seeds 5-20 0.09%
Yam Seeds.png
Yam Seeds 5-20 0.09%
Cranberry Seeds.png
Cranberry Seeds 5-20 0.09%
Beet Seeds.png
Beet Seeds 5-20 0.09%
Spring Seeds.png
Spring Seeds 5-20 0.09%
Summer Seeds.png
Summer Seeds 5-20 0.09%
Fall Seeds.png
Fall Seeds 5-20 0.09%
Winter Seeds.png
Winter Seeds 5-20 0.09%
Cactus Seeds.png
Cactus Seeds 15 1.19%
Cherry Bomb.png
Cherry Bomb 15 3.6%
Red Slime Egg.png
Red Slime Egg 1 1.8%
Seafoam Pudding.png
Seafoam Pudding 1 1.8%
Purple Slime Egg.png
Purple Slime Egg 1 3.6%
Energy Tonic.png
Energy Tonic 2-4 2.41%
Spicy Eel.png
Spicy Eel 5 1.19%
Crab Cakes.png
Crab Cakes 5 1.19%
Iridium Bar.png
Iridium Bar 2-3 3.6%
Autumn's Bounty.png
Autumn's Bounty 5 0.24%
Pumpkin Soup.png
Pumpkin Soup 5 0.24%
Super Meal.png
Super Meal 5 0.24%
Cranberry Sauce.png
Cranberry Sauce 5 0.24%
Stuffing 5 0.24%
Farmer's Lunch.png
Farmer's Lunch 5 0.24%
Survival Burger.png
Survival Burger 5 0.24%
Dish O' The Sea.png
Dish O' The Sea 5 0.24%
Miner's Treat.png
Miner's Treat 5 0.24%
Roots Platter.png
Roots Platter 5 0.24%
Prismatic Shard.png
Prismatic Shard 1 3.6%
Crystalarium 1 3.6%
Seed Maker.png
Seed Maker 1 3.6%
Auto-Grabber 1 3.6%
Red Cowboy Hat.png
Red Cowboy Hat 1 1.8%
Blue Cowboy Hat.png
Blue Cowboy Hat 1 1.8%
Mystery Box.png
Mystery Box 5 3.6% (Foraging Mastery not claimed)[7]
Golden Mystery Box.png
Golden Mystery Box 5 3.6% (Foraging Mastery claimed)[7]
White Turban.png
White Turban 1 3.6%
Auto-Petter 1 3.6%
Dark Cowboy Hat.png
Dark Cowboy Hat 1 3.6%


After reading Secret Note #10, the player will find Mr. Qi at floor 100 of the Skull Cavern. A cutscene ensues in which:

Mr. Qi will either congratulate the player for reaching floor 100 while using 10 or fewer Staircases or say the player is "clever" but not "honorable" for using more than 10. In either case, he will award the player with Iridium Snake Milk, which permanently increases the player's health by 25 points.



  • The plaques that can be occasionally found on the walls contain enciphered messages.
  • To reach the deepest floor of Skull Cavern, the Quarry Mine Floor would need to be bypassed, which has no ability to produce a ladder. This floor is coded as 77377, and can be found at floor 77257 of the Skull Cavern, (which counts floor 1 as floor 121 internally).[8]
  • Starting at floor 880, Iridium Bats will become red bats and have double health and faster speed.[9]


  1. The integer limit is 2147483647. The deepest level of Skull Cavern is 2147483527 (Because Skull Cavern is coded as floor 121 of the Mines) To reach that limit in one Stardew Valley day, the player would have to descend over 2 million floors per real-time second.
  2. See MineShaft::enterMineShaft in the game code.
  3. See MineShaft::getExtraMillisecondsPerInGameMinuteForThisLocation and Game1::UpdateGameClock in the game code.
  4. 4.0 4.1 See MineShaft::loadLevel in the game code.
  5. See MineShaft::getTreasureRoomItem in the game code.
  6. 6.0 6.1 The "Volcano Shortcut" is the shortcut between the Volcano entrance and Floor 10 (the Caldera).
  7. 7.0 7.1 7.2 7.3 Mystery Boxes are considered available once the player has viewed the Mr. Qi plane cutscene.
  8. See Locations.MineShaft::quarryMineShaft in the game code.
  9. See StardewValley.Bats::Bat in the game code.