Sand elemental: they can turn their body to sand to trap prey or avoid physical damage. 
Venom: they have a potent venom that they can spit as an acid to dissolve prey, or inject as a poison.

Constrict: the viper wolf attempt to constrict the target as sand. The target must make a strength DC of 20 or be restrained, and take 1d6 bludgeoning damage at the start of each of the viper wolf’s turns.

Bite: +6 to hit, the viper wolf attempts to bite a target for 2d8 piercing damage, and the target must beat an 18 constitution save or be poisoned and take 1d4 poison damage for the next three turns or until it passes it’s save. 

Acid spit: +6 to hit, range of 35 feet, the viper wolf pools it’s venom and spits it out as a corrosive acid, dealing 2d6 acid damage on a hit, and an additional 1d6 acid damage at the start of each of the target’s turns for 3 turns or until the acid is removed as an action. 

Multiattack: the viper wolf attempts two bite attacks and attempts to construct the target 

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Sand shift: the viper wolf shifts it’s body to sand to avoid a physical attack made against it

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Legendary Action Name (Costs # Actions). Enter the description for your legendary action.

Enter the description for how mythic actions work for your monster here.

Mythic Action Name (Costs # Actions). Enter the description for your mythic action.