Elder Grootslang (5e Creature)
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Huge monstrosity, chaotic evil
Saving Throws Str +14, Dex +4, Con +14, Wis +5
Tunneler. The worm can burrow through solid rock at half its burrow speed and leaves a 10-foot-diameter tunnel in its wake.
Electric Body. A creature that touches the Grootslang or hits it with a melee attack while within 5 feet of it takes 10 (3d6) lightning damage.
Trampling Charge. If the grootslang moves at least 20 feet straight toward a creature and then hits it with a gore attack on the same turn, that target must succeed on a DC 20 Strength saving throw or be knocked prone. If the target is prone, the grootslang can make one stomp attack against it as a bonus action.
Gore. Melee Weapon Attack: +14 to hit, reach 10 ft., one target. Hit: 28 (4d8 + 10) piercing damage.
Stomp. Melee Weapon Attack: +14 to hit, reach 5 ft., one prone creature. Hit: 32 (4d10 + 10) bludgeoning damage.
Bite. Melee Weapon Attack: +14 to hit, reach 10 ft., one target. Hit: 29 (3d12 + 7) slashing damage, and the target must make a DC 20 Constitution saving throw, taking 22 (4d10) poison damage on a failed save, or half as much damage on a successful one. If the target is a creature, it is grappled (escape DC 20). Until this grapple ends, the target is restrained, and the grootslang can't bite another target.
Acid Spray (Recharge 5-6). The grootslang spits acid in a line that is 30 feet long and 15 feet wide, provided that it has no creature grappled. Each creature in that line must make a DC 17 Dexterity saving throw, taking 30 (10d6) acid damage on a failed save, or half as much damage on a successful one.
Swallow. The grootslang makes one bite attack against a Medium or smaller creature it is grappling. If the attack hits, that creature takes the bite's damage and is swallowed, and the grapple ends. While swallowed, the creature is blinded and restrained, it has total cover against attacks and other effects outside the grootslang, and it takes 21 (6d6) acid damage at the start of each of the grootslang's turns.
When the world was young and the gods were born they tried to fill the land with various beasts, tragically many of these beings were monstrous and abominations. One beast was the direct ancestor of great serpents and elephants but he was shunned by the ancestral gods and was cursed to dwell deep below the earth hidden under the sands of the great deserts or in the cavernous places below the earth. It is said on moonless nights and days when the sky is covered with thick fog do these horrific beasts erupt from below the earth to trample foes and devour them whole. What makes a grootslang terrifying is that they enjoy killing not for food but for sheer sadistic pleasure. Grootslang look like a horrific cross between a python and a bull elephant, they have powerful jaws with razor sharp teeth but with two massive tusks that jut out from the sides of their mouths, they have a long serpentine body but their skin is covered with incredibly thick, grey and wrinkly hide just like an elephant.
What is truly unusual of the grootslang is their facial features; none of them have a similar face. Some of them appear more like great pythons with some elephantine features while others appear more like elephants but with a few snake features. It is said that some grootslang are known to even have pachyderm feet and ears like an elephant, and they crawl about the deep jungle floor like massive grey centipedes and are incapable of burrowing. The most common grootslang is the serpentine ones that can be found in the desert dunes, oasis lakes and deep caverns of the savannah.