Skull Cavern
 Warning: Spoilers  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. |
- For ladder/chute 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.
Overview
There is no limit to the number of floors, or 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 player can sometimes find a shaft, or hole, which makes it possible to skip 3-15 floors. Jumping down the shaft causes health damage equal to 3x the number of levels skipped (although jumping down a shaft will never reduce health to less than 1).
Unlike the Mines, there is no elevator to save progress, but on every floor there is a ladder at the starting point where you can leave the Skull Cavern. Each visit must start again from the first floor. 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 
1,000g will be deducted for emergency surgery. Some items may also be lost. Passing out at 2:00 am will cause the player to lose 1,000g or 10% of funds, whichever is less.
Iridium
The chance to find Iridium Ore increases steadily as you descend into the Skull Cavern. The monsters in the Cavern also have a chance to drop 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 ore veins and the appearance of ladders/holes. Rapid descent to floors with a higher chance of spawning Iridium Nodes is often more efficient for acquiring ore than thorough exploration. Staircases can be stacked, so a single inventory slot can hold 999 staircases. Even blindly placing staircases will take some time though; the lower you descend with staircases, the less time you have to explore.
Qi's Challenge
After entering the Cavern for the first time, a letter is 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 10,000g, delivered by mail the following day. If the player reaches level 25 of the Skull Cavern during the first visit, the quest will automatically be fulfilled the next day.
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. The use of Staircases is permitted. Completing the quest awards 
40 Qi Gems.
Time
Time runs more slowly in Skull Cavern than elsewhere in the game: whereas one hour of game time normally lasts 42 seconds, in Skull Cavern one hour lasts 54 seconds. However, time reverts to normal 42-second hours in multiplayer games and on Prehistoric Floors.[2] 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, however, 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 Skull Cavern.
Strategy
Food
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 and Triple Shot Espresso are an exception to this rule; they will stack with other food buffs (but not each other).
Explosives
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 |  Copper Ore (4) Coal (1) |
300g
|
 |
Bomb |  Iron Ore (4) Coal (1) |
600g
|
 |
Mega Bomb |  Gold Ore (4) Solar Essence (1) Void Essence (1) |
1,000g
|
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 300g.
Staircases
- Staircases can be used for rapid descent or skipping troublesome floors. If the player has access to one or more Crystalariums, it can be considered to make them produce Jade which can be traded for Staircases with the Desert Trader on Sundays.
Rings
Warp Totems
- A Warp Totem can be used to make a quick exit if supplies are running low or the day is almost over.
Monsters
| Image | Monster | HP | Damage | Notes |
|---|---|---|---|---|
 |
Armored Bug | 8 | Cannot be killed without bug killer enchantment. | |
 |
Big Slime | 60 | 5 | A chance to split into smaller Slimes when killed. Big Slimes are usually purple in the Skull Cavern. |
 |
Purple Slime | 410 | 28 | Can drop Iridium Ore, Iridium Bars |
 |
Lava Bat | 80 | 15 | Appears rarely; flies. |
 |
Mummy | 260 | 30 | 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. |
 |
Serpent | 150 | 23 | Moves quickly; default flying enemy. |
 |
Iridium Bat | 300 | 30 | Appears at level 50+. Very high HP and Damage. |
 |
Iridium Crab | 240 | 15 | Appears at level 26+. |
 |
Carbon Ghost | 190 | 25 | May appear on Mummy levels. Frequently drop Omni Geodes. |
 |
Pepper Rex | 300 | 15 | Appears mainly on prehistoric floors; breathes fire. |
 |
Armored Bug (dangerous) | 250 | 20-27 | Only appears when the Skull Cavern is in a "dangerous" state. |
 |
Mummy (dangerous) | 445 | 38-55 | Only appears when the Skull Cavern is in a "dangerous" state. |
 |
Royal Serpent | 675 | 28-41 | Only appears when the Skull Cavern is in a "dangerous" state. |
 |
Purple Slime (dangerous) | 403 | 20-30 | Only appears when the Skull Cavern is in a "dangerous" state. |
Prehistoric Floors
Prehistoric floors are a type of infested floor containing mainly Pepper Rex monsters. Mutant flies and Iridium Bats can also attack the player there. Dinosaur Eggs and Fiddlehead Ferns can be foraged on Prehistoric floors. Foliage on this floor has a chance to yield Ancient Seed when cut down. Below floor 6 there is a ~2.2% chance to encounter a prehistoric floor.[3]
Treasure Rooms
Small rooms containing treasure chests, similar to those in The Mines, can randomly appear at level 10+. Daily luck and Luck Buffs affect the chance to find Treasure Rooms. Obtaining the Special Charm also increases the chance to find Treasure Rooms.
Below is a collapsible table of all possible treasures that can be randomly found inside Treasure Chests in the Skull Cavern.
Secret
After reading Secret Note #10, the player will find Mr. Qi at level 100 of the Skull Cavern. A cutscene ensues in which:
| Details |
|---|
| Mr. Qi will either congratulate the player for reaching level 100 while using 10 or less 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. |
Trivia
The plaques that can be occasionally found on the walls contain enciphered messages.
Bugs
If a treasure floor spawns on a floor that is divisible by 20 but not by 40 (i.e. 20, 60 etc.), the chest will be spawned 4 tiles down, and be mostly hidden behind the wall.
History
- 1.3: Added Carbon Ghost, Iridium Bat, Iridium Crab, treasure rooms, and encounter with Mr. Qi. Removed exploit that allowed the player to avoid bomb damage by consuming food after placing a bomb.
- 1.4: Added Pepper Rex. Added White Turban to possible Treasure Room items. All players entering a chute in Multiplayer now descend to the same level. Qi's challenge can now be completed during the first visit to the Skull Cavern. Chutes will no longer drop the player past level 100 if the Secret Note cutscene has not occurred.
References
- ↑ The integer limit is 2147483647. In order to reach that limit in one Stardew Valley day, you would have to descend over 2 million levels per real-time second.
- ↑ See MineShaft::getExtraMillisecondsPerInGameMinuteForThisLocation and Game1::UpdateGameClock in the game code.
- ↑ See MineShaft::loadLevel in the game code.
- ↑ See MineShaft::getTreasureRoomItem in the game code.
| Locations | |
|---|---|
| Locations | Backwoods • Beach • Bus Stop • Calico Desert • Cindersap Forest • Farm • Farm Cave • Farm Pond • Graveyard • Ginger Island • Mastery Cave • Minecart • Mines • Mountain • Mutant Bug Lair • Pelican Town • Quarry • Quarry Mine • Railroad • Secret Woods • Sewers • Skull Cavern • Summit • Tunnel • Volcano Dungeon • Witch's Swamp |