Up to 1 minute
You draw a new sort of Wurm into the world within 5' of you. This Wurm has statistics of a Purple Worm with a challenge rating of 10 and HP of 155. You may only have 1 Wurm in the world at a time. If concentration is broken, the caster loses control of the Wurm and it cannot be regained. The Wurm has a 50% chance of attacking the nearest creature (friend or foe) and 50% chance of disappearing into a hole in the ground. While in control, the caster can use an action to send the creature away, at which point it will burrow into the ground and disappear. If spell duration ends, the Wurm will flee underground.
If you cast this using a 9th level spell slot, when this Wurm dies, you may use your reaction to cast it again.
a bit of stool from a Wurm
Invito Vermis Fistula