On screen for the table · tap DM Tools for dice, tracker, clocks, calendar and timers · press ? for keyboard shortcuts · Player casts a spoiler-safe view to a TV · Ctrl/Cmd + P prints on a light, ink-friendly layout.
A Creature Keeper · Long Island Dungeon Master
A free CR 3 monster that lives under the ice of the lake the road crosses. It sees you through the black ice, and it reaches you only through the thin.
At a glance: CR 3 · levels 3 to 5 · a lake the road crosses on the ice · it sees through the black ice and comes through the thin.
The lake is a mile of white with a line of stakes and rags bending away east across it. Nearer, the wind has taken the snow off in long bars, and the ice there is black and clear with the bottom somewhere under it. North, where the stream comes in, the ice is grey and wet-looking in a ring, with no snow on it at all. Somewhere out in the middle, under everything, the lake rings once, like a pipe struck with a hammer.
A rimejaw lives under the ice of the lake the road crosses. It sees through black ice and cannot break it. It breaks thin ice and cannot see through white. All three kinds of ice can be told apart from the shore, so the encounter is on the table before anybody steps off the land.
Cold. A creature that ends its turn in the water takes 3 (1d6) cold damage. The rimejaw does not.
Breath. A creature in the water can breathe only at a hole in the ice. The book's rule on holding breath applies as written: 1 + Constitution modifier minutes, then Constitution modifier rounds, then 0 hit points.
Out. Climbing out of the water onto ice that holds costs 10 feet of movement and both hands. A creature in the water that is more than 10 feet from a hole has to swim to one first, and swimming without a swim speed costs 2 feet of movement for every foot.
Target band levels 3-5. One rimejaw: raw 700, adjusted 700 at the single-monster multiplier of 1.0. Two rimejaws: raw 1,400, adjusted 2,100 at the two-monster multiplier of 1.5. Every figure run at the encounter calculator.
One rimejaw against four 3rd-level characters is 700 adjusted against thresholds of 300 / 600 / 900 / 1,600, a Medium encounter, and it is under the ice from the first round with nothing arriving later. The same rimejaw is Easy on paper at 4th level (500 / 1,000 / 1,500 / 2,000), and the water does the rest. At 5th level run two, a pair hunting the inlet in a hard winter: 1,400 raw at the two-monster multiplier of 1.5, so 2,100 adjusted against 1,000 / 2,000 / 3,000 / 4,400, which is Medium, both under the ice from the first round.
Open DM Tools. The rimejaw is already sitting in the combat tracker with its tactics attached, and the d12 rolls from the table roller. There are no preset clocks in this one; the three kinds of ice do that job on the map.
Senses. Darkvision 60 ft., passive Perception 11.
Drawn to. Anything that walks on the black ice in a hard winter.
Challenge. 3 (700 XP) · a crossing for levels 3 to 5
Under the Ice. The rimejaw sees creatures on clear ice above it as if the ice were not there. It cannot break ice a hand thick or more; it surfaces only through thin ice or open water, and it breathes water.
Cold Blood. The rimejaw is immune to cold damage.
Multiattack. The rimejaw makes one Bite attack and one Tail attack.
Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 14 (2d10+3) piercing damage.
Tail. Melee Weapon Attack: +5 to hit, reach 10 ft., one target. Hit: 7 (1d8+3) bludgeoning damage, and a target in the water is pushed up to 10 feet in a direction of the rimejaw's choosing.
Breach (Recharge 5-6). The rimejaw drives upward through thin ice within 5 feet of it. The ice breaks in a 10-foot square, and each creature standing on that ice makes a DC 13 Dexterity saving throw. On a failure the creature takes 7 (2d6) bludgeoning damage and falls into the water. On a success it takes half as much damage and moves 5 feet onto the nearest ice that holds.
Roll it here.
It follows under the black ice and breaches under the thin. In the water it bites what is in the water, and the Tail puts the swimmer under thick ice, away from the hole. It withdraws at 24 hit points or with a body.
Allow me. I spent a long winter once as a chest in a cold cellar, and I learned the trick of lying still under something hard and letting the warm thing come to me. This one has done the same with a whole lake. It does not chase. It follows the shadow and lets the ice do the arguing, and the ice has all winter while the party has a mile. Do not hurry the knock, fellow predator. Let them hear it twice. The second time is the seasoning.
The standard kit against a thing under the ice, and the ruling on each.
Walking round. Two days through drifts, no roll. The lake is the road, and it is not the only road.
The stakes. The carriers' route is white ice all the way and the rimejaw never comes through it. A party that follows the rags adds a mile and meets nothing. The table below puts things on the black ice; where the party walks is its own business.
A pole. A character who walks at half speed and sounds the ice ahead with a pole or a spear butt finds thin ice before stepping on it. No check.
A rope. Fifty feet of rope tied between two characters before the ice breaks, with a piton in the thick ice if they have one: the one on thick ice pulls the one in the water to the hole in one action, no roll. A rope thrown after the ice breaks is a rope the swimmer still has to reach.
Fire. A fire built on the ice melts a ring around itself in an hour, and the ring is thin ice.
Arrows and bolts. A creature under thick ice has total cover from everything above it. A rimejaw in a hole is an ordinary target. A ranged weapon attack made underwater misses automatically beyond the weapon's normal range, unless the weapon is a crossbow, a net or a thrown weapon such as a javelin.
A sword in the water. Underwater, a melee weapon attack has disadvantage unless the weapon is a dagger, javelin, shortsword, spear or trident. The rimejaw's bite is not a weapon and takes no penalty.
Shatter. Ten feet of thunder that damages objects. Cast on thick ice, the ice in the radius is thin ice now, and the rimejaw can Breach through it. Cast on the ice the party is standing on, every creature in the radius makes the Breach's Dexterity save.
Fire bolt and burning hands. A hole a foot across per casting. The rimejaw does not fit.
Fly. Sixty feet a round for ten minutes is six thousand feet, which crosses the mile with about seven hundred feet of spell to spare, for one creature, in a straight line.
Levitate. Lifts a character off the ice and holds it over the hole for ten minutes with no way to move sideways. It saves the character and ends the crossing.
Misty step. Takes a character from the water to any ice within thirty feet, wet and standing, with no climbing.
Water walk. A character who goes through the ice stands up on the open water in the hole. The rimejaw cannot pull the character under, and can bite the character's feet.
Water breathing. The breath rule goes away. The cold rule does not.
A familiar. An owl over the lake sees the shadow through black ice from above.
Speak with animals. The elk at the inlet know exactly what is under the ice, and say so.
A ranger or a druid. Survival reads the three kinds of ice from the shore without a check, and so does anyone who has read this page. The skill buys the knock's meaning: one creature, and how big.
Detect magic and divine sense. Nothing to find. It is an animal.
Things seen on the crossing. Roll once per crossing, or pick one.
| d12 | What is in the ice |
|---|---|
| 1 | An elk, head down, the antlers through the ice from below and the rest of it under. |
| 2 | A sledge with its runners up and a load of cut peat still roped on. |
| 3 | A hole the width of a cart, refrozen grey, with a ring of older white ice around it. |
| 4 | A rope frozen into the surface, running forty feet in a straight line and then going down. |
| 5 | Fish, hundreds of them, small and silver, a foot under the clear ice, all facing the same way. |
| 6 | A boot, upright, laces tied, two inches under the ice. |
| 7 | A line of wolf tracks that walks out from the shore, stops, and walks back on top of itself. |
| 8 | A column of bubbles held in the ice like a string of white beads from the bottom up. |
| 9 | A man's hand, flat against the underside of the clear ice, white, the rest of him in the dark. |
| 10 | A flat-bottomed boat frozen in level with the surface, its oars shipped. |
| 11 | A cart horse, whole, standing on the bottom of the lake in clear water forty feet down. |
| 12 | A bar of open black water ten feet wide, running straight across the way, with steam on it. |
Kester Bowyer walks the staked route every morning of the winter with a pole, sounding the ice and moving the stakes. He has done it for nineteen years and he has moved the route eleven times. He knows the rimejaw by the note it makes, he has seen it twice, and he does not talk about either time. He will tell a party where the route goes, and he will not go with them.
Kester Bowyer · walks the staked route every winter morning with a pole and moves the stakes
Wants. To keep the route on white ice, and to keep his own name out of anyone's story about the lake
Voice. Short answers. Points with the pole. Says a thing once
Line. “The straight way is the quick way for one of you.”
There is a fourth spring this winter. A grey ring forty feet across, a hundred yards east of the stakes, that was not there last year. He found it with the pole eight days ago. He has told nobody, because the only way to stake the route round it puts two hundred yards of the route onto black ice, and he has not decided which of the two he would rather have the carriers walk.
This whole page is a Creature Keeper: one file, offline, no account, yours to keep. Drop it into Gnasher's Grimoire, the free Dungeon Master companion at longislanddungeonmaster.com/grimoire, and the rimejaw, the table and the witness land on your shelf beside everything else you run from.
Compatible with fifth edition. Portions derived from the System Reference Document 5.1, © Wizards of the Coast LLC, licensed under Creative Commons Attribution 4.0 International (CC-BY-4.0). Rimejaw, Skelder Water and Kester Bowyer are original content © Long Island Dungeon Master, free to use at your table and in your own work under CC BY 4.0.
Free, offline, and yours to keep. If this file was passed to you, you can pick up your own copy and the rest of them for nothing: this Keeper's own page · more free Keepers · Gnasher's Grimoire, the free app that runs them.
Auto-built from every data-dc, data-hp, stat block, preset clock and pre-loaded combatant in this file. Prints on its own sheet.
| ? | show / hide this overlay |
| r | roll a d20 (honors adv/dis) |
| n | next turn in the tracker |
| t | open / close DM Tools |
| p | Player Mode on / off |
| 1 to 9 | jump to scene |
| Esc | close drawer / overlay |