Monster Kelp

The Monster Water Kelp, simply named Tentacles by the developers, is a stationary predator in Rain World often found around bodies of water. This creature is a consistent obstacle to forward progression until its pattern of attack has been learned. It can be found in the Drainage System, Subterranean, Shoreline, and Shaded Citadel.

= Appearance = Kelp appears like a stalk from a kelp forest, but with a tinge of green or red (appearing black in the Shaded Citadel) on the ends of its leaves. When not hunting prey, it will stand perfectly still. When something enters its range, it will lean toward it until it grabs it, and then retreat underground with its prey. If it's near, the faint sound of rustling leaves can be heard.

= Strategy = The Kelp have a short range in which they will grab the Slugcat if it strays near. If in water, can sometimes reach onto land, and can grab and eat Slugcats with ease, so practice caution around Kelp. The Kelp respond to vibrations at the water's surface and can only grab you with their hanging tendrils, so a viable strategy is to wait near one until the water becomes still and then swim under it, past the stalk.

Avoiding
In order to avoid Kelp, carry around a rock at all times. If you encounter a kelp, throw a rock at it and run past, as it will flail uncontrollably, unable to grab anything for a few moments. If there are bats in your area, grab one and release it near the Kelp. It will follow bats that fly above it, giving the Slugcat some time to run past it.

Combat
If a Kelp is hit with a spear multiple times, it will retreat underground and not appear again for many cycles. To get rid of a Kelp, attack it with a spear, run to it and pull the spear out and retreat. Repeat this until it retreats underground. If done correctly, no Kelp should appear in that spot for a few cycles, making it easier for the Slugcat to explore.

= Tips and Trivia =
 * Harmful explosives will cause Kelp to retreat underground in one shot.
 * While Kelp are only found in regions with lots of water, they can be located on land, and sometimes even on ceilings.
 * If the Slugcat is carrying a Glowstone, there is a chance a Kelp will drag it under the ground to eat, instead of the Slugcat.
 * Kelp will follow centipedes near it, but cannot grab and eat them. It is unknown if this a bug or not.
 * Developer commentary on the design of this creature and Daddy Long Legs can be found here.