The whip initially appears as a single piece of wood that has been fashioned into a rod of sorts, almost like the handle of a sword that is missing the pommel, hilt, and blade. 

When a druid of 8th level or higher attunes to it, a 10 foot long strand of green fibrous material extends like a vine until it reaches about 10 ft. This vestige stays that way as long as the user is attuned, but can be retracted using a bonus action. 

The whip is long, green, and has  an almost plant-like texture. Across the whip are a myriad of thorns that are orange, fade to white towards the tips, and have a waxy texture. The grip is sturdy, yet simple, almost as though it was carved from a single piece of wood. The wood is of unknown origin. The vine does not seem attached to the wood by crafting, and seems to be an extension of the wood itself, as though the wood is the growing point for the vine.

When attacking, the vine seems to grow another 5 ft., extending its reach to 15 ft. The whip grants a +2 to attack roles, deals 2d6 slashing damage, and on a hit, forces the target to make a DC 16 Constitution saving throw. On a fail, the target takes 4d4 poison damage, or half as much on a successful save. 

As an action, the user may also choose to crack the whip in the direction of an enemy, shooting out a thorn that deals 1d4 piercing damage. This thorn, however, due to the crack of the whip pushing more poison towards the tip of the vine, is imbued with a much more concentrated poison. The target, if hit, must make a constitution save with a DC of 17, taking  8d4 poison damage on a failed save, or half as much on a success. 

Proficiency with a Whip allows you to add your proficiency bonus to the attack roll for any attack you make with it.

Notes: Damage: Piercing, By a druid of 8th level or higher, Finesse, Reach, Slow