Blood Crawler (5e Creature)
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Large monstrosity, lawful evil
Spider Climb. The blood crawler can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.
Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one creature. Hit: 7 (1d8 + 3) piercing damage, and the target is grappled (escape DC 13). Until this grapple ends, the target is restrained, and the blood crawler can't bite another target.
At the start of each of the crawler's turns, the target loses 7 (1d6 + 4) hit points due to blood loss.
Most arachnids operate independently, but ones touched by the Crimson, the region surrounding the brain of Cthulhu's lair, coordinate together to consume life. These giant spiders have abdomens bloated with blood and large, unsettlingly human eyes clouded with cataracts. They seem to arise when mites or other parasitic arachnids enter the Crimson and feast on the abundant flesh and blood. Blood crawlers prefer to live underground, feeding quietly until disturbed.