A Free Creature Keeper · Long Island Dungeon Master
Thirstthorn
A CR 3 plant that cannot move, cannot chase you, and will take the whole party if one person crawls.
One file, running in your browser. The thorn is already in the initiative tracker with its tactics attached, all three clocks are built, and both tables roll themselves. Offline, no account, yours to keep.
Or take the print PDF or open the PDF in your browser firstEleven pages, with the stat block whole on one page, both tables intact, and a player handout alone on the last sheet so you can tear it off and hand it across the table.
Most traps in this hobby lie to the party, and a party that has been lied to three times stops walking into anything. This one tells the truth. A thirstthorn grows in a ring around real water, in country where real water is the only thing anybody is looking for, and from a mile out it reads exactly as what it is: shade, green stalks, and a pool you can hear from where you are standing. Every word of that is true. The catch is the last twenty feet. The only way to the pool is a three-foot tunnel through the stalks, and a Medium creature goes in at half speed with both arms out in front and a sword it cannot swing, while everybody else stands in the open air watching the tunnel mouth with no way to reach anybody. Fire kills it in under a minute. Fire also cooks the pool, which is the one thing the party came here for, and they work that out by round two. You get the full stat block, a d20 of what the thorn has already drunk (every row a condition the plant is currently in, not loot), a d12 of what happens when they bring fire, a witness worth talking to, a print-ready PDF with a player handout, and a Keeper that runs the whole thing from a browser tab. Free to use at your table under CC BY 4.0.
d20, 11. A surveyor with a full satchel. It drank him and kept the rest. The satchel is in the pool, waterlogged and legible, and it holds a working chart of every reliable water source for two hundred miles.
d20, 16. A pilgrim who is still alive in there. Four days in, Grappled, conscious, at 2 hit points, and quiet because he stopped shouting on the second day.
d12, 12. Whoever lit it is still holding the torch in a three-foot tunnel. The character who solved the problem is now the character in the worst position in the encounter, and they did it to themselves on purpose.
While you’re here
Gnasher’s Grimoire
The free Dungeon Master companion on itch.io: your reference, your rolls and your trackers open on the screen while you play. The Creature Keeper above installs straight into it.
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The same Grimoire, running in this browser. Nothing to install, nothing to sign up for.
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Open it →Long Island Dungeon Master
The adventures are mine. 30+ years of real tables. Compatible with fifth edition. Portions derived from the SRD 5.1, © Wizards of the Coast LLC, under CC-BY-4.0. Thirstthorn is original © Long Island Dungeon Master, free to use at your table and in your own work under CC BY 4.0.