Shivergeist (5e Creature)
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Medium undead, any alignment
Skills Stealth +3
Ethereal Sight. The shivergeist can see 60 feet into the Ethereal Plane when it is on the Material Plane, and vice versa.
Illumination. The shivergeist sheds dim light in a 20 foot radius.
Incorporeal Movement. The shivergeist can move through other creatures and objects as if they were difficult terrain. It takes 5 (1d10) force damage if it ends its turn inside an object.
Silence. The shivergeist produces no sound unless it chooses to.
Etherealness. The shivergeist enters the Ethereal Plane from the Material Plane, or vice versa. It is visible on the Material Plane while it is in the Border Ethereal, and vice versa, yet it can't affect or be affected by anything on the other plane.
Frost Bite. Melee Weapon Attack: +6 to hit, reach 10 ft., one target. Hit: 13 (3d8) piercing damage, and the target must make a DC 15 Constitution saving throw. On a failed save, it becomes poisoned; while poisoned this way, the target has a -1 penalty to their Dexterity modifier and takes 6 (2d4 + 1) necrotic damage at the start of each of its turns. If someone uses an action and makes a successful DC 12 Wisdom (Medicine) check, the target is no longer poisoned.
The ghost of a long-dead predator. This silent, graceful specter seems almost peaceful, keeping its distance from its prey and often lurking out of sight until an opportunity to jab with its more tangible, fused jaw. Each slender fang is repeatedly slathered with the monster's poisonous salivary secretions, turning the single jaw into a venomous stinging appendage. The toxins of the shivergeist are characterized by extremely rapid necrosis, uncontrollably shaking and the false sensation of debilitating cold, making victims appear stricken with sudden, progressive frostbite in even the warmest surroundings; its preferred source of food is the fingers, ears or other small, swallowable morsels that drop off its withering victims.