A strange animated plant that entangles and constricts prey to fertilize its soil

A strangle vine (sometimes called an assassin vine) is a strange animated plant found in temperate and tropical forests, particularly in areas with poor-quality soil. They fertilize their soil by entangling, constricting, and killing living creatures, then depositing the bodies in loose soil around the plant's base. Because it can lie very still indeed, a strangle vine surprises on a roll of 1-4 on 1d6. A successful hit inflicts 1d8 points of damage, and the victim becomes entangled, suffering an additional 1d8 points of damage thereafter. A victim may attempt to escape by rolling a saving throw vs. Death Ray with Strength bonus added; this is a full action, so the victim may not attempt this and also perform an attack. The plant will continue to crush its victim until one or the other is dead or the victim manages to escape. Strangle vines are actually mobile, able to uproot themselves and move slowly from place to place; one generally only does so to seek new hunting grounds. They have no visual organs but can sense foes within 30 feet by sound and vibration. Each plant consists of a single long vine of up to 20 feet in length, with many smaller vines 5 feet or so in length pa