Invasion from the Planet of Tarrasaques

You can order The Demonplague, my level 1 – 20 fifth edition adventure, right now!

I’ve got a new DMs Guild product! It’s an adventure for level 20 characters… and it has more than fifty tarrasques! (You read that correctly.) Behold the product description of Invasion from the Planet of Tarrasques!

Invasion from the Planet of Tarrasques is a single-session, over-the-top, gonzo action adventure meant for four to six level 20 characters. The adventure serves as a capstone for Waterdeep: Dragon Heist and Waterdeep: Dungeon of the Mad Mage, but can be modified for any setting.

What’s more fun than one tarrasque? How about multiple tarrasques stomping across Waterdeep? How about a whole planet full of tarrasques ready to rumble? If that sounds exciting, then Invasion from the Planet of Tarrasques is for you.

Halaster Blackcloak died… but then he came back… with reinforcements…

Adventure Background

Halaster Blackcloak, the Mad Mage of Undermountain, always has a contingency in place. As long as Undermountain remains beneath the city of Waterdeep, Halaster can never truly die within its walls, for the dungeon rebuilds the mage’s body on the rare occasions when adventurers “kill” Halaster.

Halaster realized that if adventurers destroyed all of Undermountain (a nigh impossible feat more difficult than even slaying the mage), he would lose his immortality. To further protect his life, Halaster took some of the rooms and halls of Undermountain and flung them across the multiverse, including other worlds of the Material Plane. With Undermountain spread across existence, the task of permanently killing Halaster is even more difficult.

Unfortunately for the mage, a party adventurers recently killed him in his dungeon beneath the City of Splendors. When Halaster’s body reformed, he found himself in Falx, another world of the Material Plane inhabited entirely by enormous, carnivorous monsters with endless appetites. These scaly bipeds are closely related to the tarrasque, an infamous monstrosity feared across the worlds of the Material Plane. Halaster, now obsessed with punishing the adventurers who killed him, began to hatch a plot. If one tarrasque could level an entire city, what could a planet’s worth of the beings do to Faerûn?

Adventure Overview

This adventure is divided into three chapters.

  • Chapter 1. In “Giff You a Hand” a platoon of giff arrive in a spacefaring vessel and warn the adventurers about a coming invasion of tarrasques. With the clock ticking, the characters have a chance to prepare for the battle by mustering their allies.
  • Chapter 2. In “Battle for Waterdeep” the characters face-off with the invading titans, defend Waterdeep, and fight for their lives.
  • Chapter 3. In “Falx, Ho!” the characters travel through a portal to the planet of Falx to face Halaster and his army of tarrasques atop a stone tower made from pieces of Undermountain.

This product includes…

  • A PDF of the adventure with art
  • A printer friendly version of the adventure
  • Map images that can be used with virtual table tops

Cover Art Shoutout

I commissioned Stacey Allan to make the cover art, which is my favorite for ANY DMs Guild product (though I am biased). Ain’t it rad?

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