Alluring Pearl. The osster's shell contains at least one shiny humanoid skull, polished and sculpted to resemble a pearl. Any non-undead creature that starts its turn within 60 feet of the osster and can see the osster must succeed on a DC 16 Wisdom saving throw or be forced to use all its movement on its turns to get as close to the osster as possible. An affected target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
Unless surprised, a creature can avert its eyes to avoid the saving throw at the start of its turn. If the creature does so, it can't see the osster until the start of its next turn, when it can avert its eyes again. If the creature looks at the osster in the meantime, it must immediately make the save.
Bone Fusion. Any beast, fey, giant, or humanoid that touches the osster or starts its turn while grappling the osster or being grappled by it must succeed on a DC 16 Constitution saving throw or else take 3 (1d6) necrotic damage and be restrained for 1 minute. A creature afflicted by fused bones repeats the saving throw at the end of each of its turns, taking no damage on a failed save, and ending the effect on itself on a success.
False Appearance. While the osster remains motionless, it is indistinguishable from an ordinary giant clam.
Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 10 (2d6 + 3) bludgeoning damage plus 7 (2d6) piercing damage and 10 (3d6) necrotic damage, and the target is grappled (escape DC 16). Until this grapple ends, the target is restrained, and the osster can't bite another target or use its Withdraw action.
Withdraw. The osster closes its shell tightly. Until it opens its shell, it gains a +5 bonus to AC, and it has advantage on Strength and Constitution saving throws. While the osster's shell is closed, its Alluring Pearl trait doesn't function, its speed is 0 and can't increase, it has disadvantage on Dexterity saving throws, it can't take reactions, and the only action it can take is a bonus action to open its shell.
Description
Though often mistaken for giant oysters or clams, the strange undead creatures known as osster shells, native to the dark waters of the Shadowfell, are more deadly than any living sea shell could ever be.
Bone-Eaters. No one knows how ossters are formed, for they are not alive and do not reproduce, and they are not merely undead oysters. They grow from a small size by filter feeding the remains of bones and other necrotic materials from the water around it, fusing them to form new layers of its skeletal shell. An osster's ability to fuse bones together is so powerful that it can even use it to defend itself from attackers. They also feed on any living prey that wanders too close, catching the prey in their jaws and killing it by beginning the bone fusion process.
Skull Pearls. The polished skulls that can be found inside an osster shell, known informally as "skull pearls" due to their similarity to real pearls, are highly prized among those who know how to utilize the necromantic magic that lurks within them. Skull pearls make such fine ritual components and arcane focuses that osster shells are hunted from time to time, and some, such as death giants or enterprising liches, even construct huge aquatic osster farms to harvest the pearls.
Aquatic Guardians. Ossters are often employed by necromancers to guard aquatic locations they wish to keep secret, such as sunken ruins out in the open sea, or the flooded passageways beneath their necromantic lair. Even the dark of the deepest underwater places are no concern, as ossters don't rely on eyes to catch prey.
Undead Nature. An osster shell doesn't require air, food, drink, or sleep.
Variant: Coral-Legged Osster Shells
Though no necromancers have yet discovered how to create ossters from scratch, many have managed to take control of them, and some are even able to modify them for the necromancer's own purposes. The most common example of these modifications is adding spindly legs made of undead coral to the bottom of the osster's shell, allowing the creature to not only walk, but to kick as well. These ossters have an increased walking speed of 20 feet, and they also gain access to the following two actions:
Multiattack. The osster makes two kick attacks.
Kick. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 10 (2d6 + 3) piercing damage plus 4 (1d8) necrotic damage.
Comments