Gutmaw
Beast -- Huge -- Deep river channels, broad estuarine basins, flooded valley floors, delta main channels
I have seen the marks it leaves when it comes out of the water. Not the animal -- we do not want to see the animal. The marks. The ground compression. The drag path where it moved from the bank back to the channel. Something large enough to leave that path does not need to be seen to be understood. The settlement has a bell system for the channel watch. Three rings means it has been seen in the main channel. Five rings means it has come out. We have not had a five-ring event in four years. The bell still works. We check it every month.
-- delta settlement operations record, channel watch station
Ecology
The Gutmaw is what the Siltjaw becomes after a few more meters and several hundred more kilograms. The scaling is not linear -- a Huge animal with 138 HP, Multiattack, and a Tail strike that hits everything within 10 feet is not just a bigger version of the smaller animal; it is a different category of problem. The Gutmaw occupies the largest river systems and deep estuarine basins where the water depth and channel width give it room to maneuver at its full scale. It does not share territory with Siltjaws in any meaningful sense; where Gutmaws are present, Siltjaws are downstream.
The Hold Breath capacity of 30 minutes reflects a physiology adapted to deep extended submersion -- not just ambush waiting, but sustained bottom movement through main channel systems that can carry the animal kilometers between surface appearances. A Gutmaw that is not in the water is an event; a Gutmaw that is in the water is present in the system but not necessarily visible. Settlements on major river systems that have Gutmaw populations treat the main channel as a managed hazard zone rather than a transit corridor.
The Tail action -- a 10-foot reach sweeping attack that can hit every creature in range rather than a single target -- reflects the mechanical reality of being near a Huge animal in water when it turns. A Gutmaw is not trying to hit multiple targets with its tail; it is a turning animal with a body that occupies significant space. The tactical implication is that clustering around the animal is as dangerous as being the primary target.
In high-saturation delta systems, Gutmaws show the same mineral secondary calcification that Siltjaws develop, but at scale -- dorsal armor plating dense enough that edged weapons on the upper body are largely ineffective, and a visual appearance that makes the animal look, from above the water, like a partially submerged debris raft. Settlement scouts learn to distinguish the two. It takes time. Some of them learn from surviving the mistake.
Stat block
| AC | HP | Speed | Initiative |
|---|---|---|---|
| 14 | 138 (12d12 + 60) | 30 ft., Swim 50 ft. | +0 (10) |
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 21 (+5) | 9 (-1) | 21 (+5) | 2 (-4) | 10 (+0) | 7 (-2) |
Skills Perception +3, Stealth +2 (+5 in water)
Senses Passive Perception 13
Languages None
CR 5 (XP 1,800; PB +3)
The Gutmaw can hold its breath for 30 minutes. The Gutmaw makes one Bite attack and one Tail attack. Melee Attack Roll: +8, reach 5 ft. Hit: 21 (3d10 + 5) Piercing damage, and the target has the Grappled condition (escape DC 16). Until this Grapple ends, the target has the Restrained condition, and the Gutmaw can't Bite another target. Melee Attack Roll: +8, reach 10 ft. Hit: 14 (2d8 + 5) Bludgeoning damage. If the target is a creature, it must succeed on a DC 16 Strength saving throw or have the Prone condition.Hold Breath
Multiattack
Bite
Tail
Encounter use
A Gutmaw encounter is an environmental crisis, not a standard fight. 138 HP, AC 14, Multiattack, and Bite that applies both Grappled and Restrained simultaneously means this animal can hold a character motionless in its jaws indefinitely while the Tail attack keeps anyone who approaches Prone. In water, a Prone character cannot stand without spending movement, which they may not have against the rest of the encounter. Use the Gutmaw to force a decision: fight it in its element and take sustained attrition, or extract the grabbed character and disengage. The animal does not leave the water to pursue. A party that can get everyone onto the bank ends the encounter; a party that cannot, or that chooses to fight, is in a position where the animal's HP is the ceiling and the party's resources are the floor. At CR 5 this should test a mid-level party seriously. The Stealth +5 in water means they may not know it is there until it has already bitten someone.
Salvage
A Gutmaw carcass is a significant event in any settlement that manages to produce one. The primary value is the dorsal plating in high-saturation specimens -- slabs of mineral-reinforced scale that exceed the hardness of anything produced by standard smithwork and that, with appropriate Lattice-assisted tooling, can be shaped into armor components of exceptional quality. The jaw is a structural element: the bite force is preserved in the bone architecture and the teeth, particularly the posterior crushing teeth, are used as industrial press components. The fat layer is substantial and renders into a waterproofing compound with applications in both construction and equipment treatment. Settlements in delta systems that have successfully hunted one will talk about it for generations.