Triffid (Triffidus Beynoni) Large Plant (Unaligned)
Armour Class: 14 (Natural armour) Hit Points: 49 (9d10)
Speed 10' (Forestwalk)
STR 12 (+1) DEX 10 (+0) CON 11 (+0) INT 3 (-4) WIS 11 (+0) CHA 4 (-3)
Skills: Natural Appearance
Condition Immunities: Blinded (see Sound Blindness), Frightened, Poisoned,
Senses: Blindsight 120' (blind beyond this distance; see Sound Blindness), Tremorsense 10' ;Passive Perception: 10
Forestwalk: The Triffid ignores difficult terrain caused by trees, bushes or other natural features found in a forested area, even if they are not caused by nature.
Natural Appearance: The Triffid gains advantage on Dexterity (Stealth) checks when hiding in forested surroundings
Sound Blindness: If deafened, the Triffid cannot use its Blindsight. If it takes Thunder damage, it must make a Constitution save (DC 10), or be blinded until the end of its next turn.
Its Tremorsense still functions normally when blinded in this manner.
Actions
Stinger: Melee weapon attack, Reach 20', +5 to hit, one target, Hit: 10 (2d8+1) slashing damage, and target is poisoned for 10 hours if they fail a D.C. 8 Constitution save.
Poisoned creatures are allowed another saving throw at the end of every hour.
Whilst poisoned, the target is also blinded. If they failed their saving throw by 5+, on the first attempt, they are also Paralysed.
Roots: All creatures within 10' of the Triffid, that do not have Forestwalk and are in contact with the ground, must make a D.C. 11 Dexterity saving throw or be knocked prone. If they fail this save by 6+, they are stunned until the end of the Triffid's next turn.
CR: 3
In almost every detail it was a half-size replica of a fully grown triffid... My father leaned over, peering at it through his horn-rimmed gasses, fingering its stalk, and blowing gently through his gingery mustache, as was his habit when thoughtful. He inspected the straight stem, and the woody bole from which it sprang. He gave curious, if not very penetrative, attention to the three small, bare sticks which grew straight up beside the stem. He smoothed the short sprays of leathery green leaves between his finger and thumb as if their texture might tell him something. Then he peered into the curious, funnel-like formation at the top of the stem, still puffing reflectively, but inconclusively, through his mustache. I remember the first time he lifted me up to look inside that conical cup and see the tightly wrapped whorl within, It looked not unlike the new, close-rolled frond of a fern, emerging a couple of inches from a sticky mess in the base of the cup....
It was some little time later that the first one picked up its roots and walked.
(John Wyndham, The Day of the Triffids, pages 15 and 16)