Tentacles are hostile Monsters that specifically spawn in Marshes or Caves, though they will not spawn on world-generated roads. Wickerbottom can summon Tentacles using On Tentacles, one of her self-published books.
When the player or mob approaches an area containing a Tentacle, bubbles will appear on the ground. Getting closer will cause the Tentacle to bulge out of the ground before extending fully. It will then try thrashing at anything within range, and will disappear back into the ground once there's no targets left.
If the Big Tentacle and the Baby Tentacles aren't attacked for a while, they eventually retreat back into the ground. Baby Tentacles are only found underground.
Baby Tentacles will fight nearby Tentacles and vice-versa.
Tentacles are very dangerous because of their high damage and high health. They can only be seen once a creature or player gets relatively close, meaning that a careless player can easily walk into an area with many Tentacles without noticing them before being stun-locked and killed.
At first, there will be a barely noticeable bubbling patch on the ground, followed by a piece of tentacle that looks like a purple bubble, which appears just before the Tentacle surfaces. When a creature is in range, the Tentacle will emerge and twirl around once before snapping and standing straight up. There is a brief delay before it strikes again, they will often hit an entity twice during their attack animation.
As long as its current target is still in range, a Tentacle will not change targets even if something else attacks it, similar to Tallbirds.
If its target moves out of range, the Tentacle will sink back down into the ground; it cannot move around or give chase. After going back underground, Tentacles will stay hidden until another target moves into range or directly hits them, at which point they begin to attack again.
Due to Tentacles' aggressive nature, it is common to find drops from creatures they kill or from dead Tentacles killed by other creatures (usually Merms), lying on the Swamps. One Tentacle can sometimes kill a group of 4 Spiders on their own, though it depends on the situation. Due to this behavior, many players like to use Tentacles as a food and item supplier, especially when camping in or near a Marsh.
Tentacles do not respawn upon death, making them a finite resource for most characters. Wickerbottom is the only character who can prevent Tentacles from becoming extinct by using the book On Tentacles. It is worth noting that even though Tentacles do not respawn, players can get the same loot from Big Tentacles.
Tentacles cannot be stun locked. With most characters, it takes 15 strikes with a Spear to kill one. If properly timed, they can be attacked in between their strikes. Although they appear to have an area attack, Tentacles actually attack targets individually. Due to this limitation, Pigs that attack if they get too close can easily kill a Tentacle if there are at least three of them.
Tentacles will still produce an Insanity aura, even if it is still in the ground and out of attack range. Thus, the sanity meter is a good indication that a Tentacle is near. Additionally, there is a low growl that can be heard when a Tentacle is near, and the player can watch for the bubbling patch, though Sanity drain is still the best indication, as the Tentacle growl can easily get confused with the normal growling ambiance of the swamp. During Adventure Mode, the sanity meter indication can be a lifesaver if the player is traveling in a swamp at dusk or night.
A safe, but time-consuming way to fight a Tentacle is to go right next to the spot where the Tentacle will come out, hit it as soon as the little nub appears, and dash to the side, out of its reach. Repeat after the Tentacle retracts into the ground.
It can be easy to kill Tentacles with little to no work by finding some Rundown Houses, waiting for Dusk, and seeing if the Tentacle alarms the Merms. The stiff fight will end in Frog Legs, Monster Meat, Fish, and perhaps Tentacle Spots, or a Tentacle Spike.
Another easy way to kill a number of tentacles is to bring 2-3 Rock Lobsters from Caves. Tentacles will attack Rock Lobsters when they are led through them. The Rock Lobster that the tentacle attacks will curl up into a boulder, negating most of the incoming damage, while the other Rock Lobsters kill the Tentacle. 2-3 Rock Lobsters are capable of cleansing entire Marsh Biomes of tentacles provided the player has enough minerals to befriend them long enough to finish the job.
To make "tentacle traps", the player must bring several Pine Cones to the swamp and plant 3-6 of them around where the Tentacle emerges. Once the trees are grown and the player is ready to harvest the tentacle, they can simply light the trees on fire and the tentacle will die before the last tree burns out, even when hidden underground. The downside is that any Tentacle Spots that drop will also burn leaving only Ashes. To avoid this, the player can use exactly 4 Logs instead, which will drain Tentacle's heath low enough to be killed with a single hit using Spear. This method of hunting is easiest with Willow due to her fire affinity. This does not, however, work in DST, where the tentacle takes no damage from the fire.
Alternatively to the method above, one can use Gunpowder. A player can place a stack of three near a tentacle, ignite them and dash away. Even when hidden underground the tentacle will die instantly in the blast. A gunpowder stack of two can also be used, but the tentacle will need to be finished off with 2 swings of a Tentacle Spike. The player is usually fast enough to kill it before it manages to attack in this case. However, this case would require 3 consecutive swings of the Spear, which will allow for retaliation after the second swing.
When fighting Big Tentacles, bringing Fugu Hutch can bring a great advantage. When Hutch is pushed next to both the player and the Big Tentacle, it protects the player with its spiky exterior. Hutch can kill Baby Tentacles within their first strike, leaving an open area near void of the Baby Tentacles' attacks. The regenerative powers of Hutch negates any damage from the Baby Tentacles.
If one cannot find Hutch, one can use the Tail o' Three Cats or Bull Kelp Whip to kill the Baby Tentacles all while staying safe from the range of the attacks. With the Baby Tentacles out of the way, the player can strike the big tentacle once more.
Below is the number of hits it takes with each weapon to kill Tentacles when playing with characters with a default damage modifier. The Weather Pain is not included due to the random nature of its projectile.
|No. of hits for||Immune||118||37||30||19||17||15||12||9 - 17||7 or 12||10||9||8||5||3||1|
In Don't Starve Together, when a Big Tentacle retreats into its hole, it won't cause an Earthquake and the big tentacle on the other side will retreat into the ground as well. The player can then travel through the hole, just like a Wormhole, Teleporting them near the hole of another big tentacle. Unlike wormholes, jumping into the hole left by the big tentacle (the "big slimy pit") will not lower the player's sanity. Eventually, the big tentacles will respawn and they can be killed again, making Tentacle Spikes and Tentacle Spots renewable.
- If the player is near a Swamp biome, the Tentacle can appear (barely) outside of its biome.
- When using the Thulecite Club, there is a chance that small Shadow Tentacles will appear and assist the player with attacking.
- Maxwell expresses surprise at the existence of the Big Tentacle and the baby Tentacles, suggesting that the Tentacles are reproducing, and were not planned to do so, as Wilson and Wickerbottom mention that Tentacle Spots are its genitalia; supported by Maxwell's quote for Tentacle Spots, 'This is how they reproduce'.
- The small tentacles that appear around the Big Tentacle used to be colored green.
- In the script that handles the Tentapillar's emergence when the hole is attacked, there is a note/Easter Egg that says: ("Hit calls cthulhu"). This is a reference to a story by H.P. Lovecraft called "The Call of Cthulhu".
- Baby tentacles are actually arms of the big tentacles, as stated by the developers when they explained why baby tentacles don't drop souls.