Rott Grass (5e Creature)
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Small plant, unaligned
Saving Throws Str +5, Con +4
Adhesive. The grass adheres to anything that touches it. A Huge or smaller creature adhered to the grass is also grappled by it (escape DC 13). Ability checks made to escape this grapple have disadvantage.
False Appearance. While the grass remains motionless, it is indistinguishable from a patch of dead grass.
Needles. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 5 (1d4 + 3) piercing damage.
Rott grass live in open planes in the middle of the forests. Originating from Feywild you may find them close to portals leading there. They wait for animals or travelers to mistakingly step on them in which point many rott grass attack at once.