Frostwurm
Gargantuan • Dragon • Neutral
Armor Class 21
Hit Points 280 (16d20 + 112)
Speed 60 ft., swim 60 ft.
Initiative +8 (18)
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 27 (+8) | 14 (+2) | 24 (+7) | 10 (+0) | 19 (+4) | 17 (+3) |
Saving Throws Str +14, Con +13
Skills Perception +10
Damage Resistances fire, poison
Damage Immunities cold
Senses blindsight 30 ft., darkvision 120 ft., tremorsense 120 ft., passive Perception 20
Languages Draconic, Primordial (Aquan)
CR 20 (XP 25,000; PB +6)
Amphibious. The frostwurm can breathe air and water.
Ice Walk. The frostwurm can move across and climb icy surfaces without needing to make an ability check. Additionally, difficult terrain composed of ice or snow doesn’t cost it extra movement.
Impervious Scales. The frostwurm has a damage threshold of 15, except against psychic damage or damage dealt by creatures swallowed by it.
Legendary Resistance (3/Day). If the frostwurm fails a saving throw, it can choose to succeed instead. When it does, its damage threshold is reduced by 5 until it finishes a long rest.
ACTIONS
Multiattack. The frostwurm makes one Bite and one Tail attack.
Bite. Melee Weapon Attack: +14, reach 15 ft. Hit: 27 (3d12 + 8) piercing damage plus 36 (8d8) cold damage. If the target is a Large or smaller creature, it is grappled (escape DC 22). While grappled this way, the target is restrained.
Tail. Melee Weapon Attack: +14, reach 30 ft. Hit: 30 (4d10 + 8) bludgeoning damage and the target is knocked prone and pushed back 10 feet.
Frost Shard Breath (Recharge 6). Dexterity Saving Throw: DC 21, each creature in a 60-foot cone. Failure: 21 (6d6) piercing damage and 45 (10d8) cold damage. Success: Half damage. Failure or Success: The area becomes difficult terrain for 1 minute for creatures other than the frostwurm, and when a creature moves into or within the area, it takes 2d4 piercing damage for every 5 feet it travels.
Ice Mist Breath. The area in a 30-foot emanation originating from the frostwurm, spreading around corners, becomes heavily obscured for 1 minute or until a strong wind (such as one created by gust of wind) disperses it. When a creature starts its turn inside the area, it takes 10 (3d6) cold damage.
BONUS ACTIONS
Swallow. Strength Saving Throw: DC 22, one Large or smaller creature grappled by the frostwurm (it can have up to three creatures swallowed at a time). Failure: The target is swallowed by the frostwurm, and the grapple ends. A swallowed creature is blinded and restrained, has total cover against attacks and other effects outside the frostwurm, and gains one level of exhaustion due to the extreme cold at the start of each of the frostwurm’s turns.
If the frostwurm takes 40 damage or more on a single turn from a creature inside it, the frostwurm must succeed on a DC 25 Constitution saving throw at the end of that turn or regurgitate all swallowed creatures, each of which falls in a space within 5 feet of the frostwurm and is prone. If the frostwurm dies, any swallowed creature is no longer restrained and can escape from the corpse using 20 feet of movement, exiting prone.
Frostwurm
Gargantuan • Dragon • Neutral
Armor Class 20
Hit Points 201 (13d20 + 65)
Speed 60 ft., swim 60 ft.
Initiative +7 (17)
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 25 (+7) | 14 (+2) | 21 (+5) | 10 (+0) | 17 (+3) | 16 (+3) |
Saving Throws Str +12, Con +10
Skills Perception +8
Damage Resistances fire, poison
Damage Immunities cold
Senses blindsight 30 ft., darkvision 120 ft., tremorsense 120 ft., passive Perception 18
Languages Draconic, Primordial (Aquan)
CR 16 (XP 20,000; PB +5)
Amphibious. The frostwurm can breathe air and water.
Ice Walk. The frostwurm can move across and climb icy surfaces without needing to make an ability check. Additionally, difficult terrain composed of ice or snow doesn’t cost it extra movement.
Impervious Scales. The frostwurm has a damage threshold of 10, except against psychic damage or damage dealt by creatures swallowed by it.
Legendary Resistance (2/Day). If the frostwurm fails a saving throw, it can choose to succeed instead. When it does, its damage threshold is reduced by 5 until it finishes a long rest.
ACTIONS
Multiattack. The frostwurm makes one Bite and one Tail attack.
Bite. Melee Weapon Attack: +12, reach 15 ft. Hit: 19 (2d12 + 6) piercing damage plus 31 (7d8) cold damage. If the target is a Large or smaller creature, it is grappled (escape DC 21). While grappled this way, the target is restrained.
Tail. Melee Weapon Attack: +12, reach 30 ft. Hit: 23 (3d10 + 7) bludgeoning damage and the target is knocked prone and pushed back 10 feet.
Frost Shard Breath (Recharge 6). Dexterity Saving Throw: DC 18, each creature in a 60-foot cone. Failure: 14 (4d6) piercing damage and 40 (9d8) cold damage. Success: Half damage. Failure or Success: The area becomes difficult terrain for 1 minute for creatures other than the frostwurm, and when a creature moves into or within the area, it takes 2d4 piercing damage for every 5 feet it travels.
Ice Mist Breath. The area in a 30-foot emanation originating from the frostwurm, spreading around corners, becomes heavily obscured for 1 minute or until a strong wind (such as one created by gust of wind) disperses it. When a creature starts its turn inside the area, it takes 7 (2d6) cold damage.
BONUS ACTIONS
Swallow. Strength Saving Throw: DC 19, one Large or smaller creature grappled by the frostwurm (it can have up to three creatures swallowed at a time). Failure: The target is swallowed by the frostwurm, and the grapple ends. A swallowed creature is blinded and restrained, has total cover against attacks and other effects outside the frostwurm, and gains one level of exhaustion due to the extreme cold at the start of each of the frostwurm’s turns.
If the frostwurm takes 40 damage or more on a single turn from a creature inside it, the frostwurm must succeed on a DC 25 Constitution saving throw at the end of that turn or regurgitate all swallowed creatures, each of which falls in a space within 5 feet of the frostwurm and is prone. If the frostwurm dies, any swallowed creature is no longer restrained and can escape from the corpse using 20 feet of movement, exiting prone.
Frostwurm
Gargantuan • Dragon • Neutral
Armor Class 22
Hit Points 351 (19d20 + 152)
Speed 60 ft., swim 60 ft.
Initiative +10 (20)
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 29 (+9) | 16 (+3) | 26 (+8) | 10 (+0) | 20 (+5) | 18 (+4) |
Saving Throws Str +16, Con +15
Skills Perception +12
Damage Resistances fire, poison
Damage Immunities cold
Senses blindsight 30 ft., darkvision 120 ft., tremorsense 120 ft., passive Perception 22
Languages Draconic, Primordial (Aquan)
CR 24 (XP 62,000; PB +7)
Amphibious. The frostwurm can breathe air and water.
Ice Walk. The frostwurm can move across and climb icy surfaces without needing to make an ability check. Additionally, difficult terrain composed of ice or snow doesn’t cost it extra movement.
Impervious Scales. The frostwurm has a damage threshold of 20, except against psychic damage or damage dealt by creatures swallowed by it.
Legendary Resistance (4/Day). If the frostwurm fails a saving throw, it can choose to succeed instead. When it does, its damage threshold is reduced by 5 until it finishes a long rest.
ACTIONS
Multiattack. The frostwurm makes one Bite and one Tail attack.
Bite. Melee Weapon Attack: +16, reach 15 ft. Hit: 35 (4d12 + 9) piercing damage plus 44 (8d10) cold damage. If the target is a Large or smaller creature, it is grappled (escape DC 24). While grappled this way, the target is restrained.
Tail. Melee Weapon Attack: +16, reach 30 ft. Hit: 42 (6d10 + 9) bludgeoning damage and the target is knocked prone and pushed back 10 feet.
Frost Shard Breath (Recharge 6). Dexterity Saving Throw: DC 23, each creature in a 60-foot cone. Failure: 27 (6d8) piercing damage and 55 (10d10) cold damage. Success: Half damage. Failure or Success: The area becomes difficult terrain for 1 minute for creatures other than the frostwurm, and when a creature moves into or within the area, it takes 2d4 piercing damage for every 5 feet it travels.
Ice Mist Breath. The area in a 30-foot emanation originating from the frostwurm, spreading around corners, becomes heavily obscured for 1 minute or until a strong wind (such as one created by gust of wind) disperses it. When a creature starts its turn inside the area, it takes 14 (4d6) cold damage.
BONUS ACTIONS
Swallow. Strength Saving Throw: DC 24, one Large or smaller creature grappled by the frostwurm (it can have up to three creatures swallowed at a time). Failure: The target is swallowed by the frostwurm, and the grapple ends. A swallowed creature is blinded and restrained, has total cover against attacks and other effects outside the frostwurm, and gains one level of exhaustion due to the extreme cold at the start of each of the frostwurm’s turns.
If the frostwurm takes 40 damage or more on a single turn from a creature inside it, the frostwurm must succeed on a DC 25 Constitution saving throw at the end of that turn or regurgitate all swallowed creatures, each of which falls in a space within 5 feet of the frostwurm and is prone. If the frostwurm dies, any swallowed creature is no longer restrained and can escape from the corpse using 20 feet of movement, exiting prone.
QUICK REFERENCE
Habitat
- Frozen wastelands, glacial caves and ice caverns
- The elemental plane of water or ice
- Beneath frozen seas and the deep oceans
Behavior
- Ancient, territorial, and cunning predator
- Hunts everything that it finds, from travelers to whole ship crews, often using blizzards or storms at sea for cover
- Rarely engages in bargaining or negotiations unless it views the counterpart as powerful
Information (Intelligence Check)
- DC 15 History: Known as a wingless dragon-like predator of frozen lands and seas
- DC 20 Nature: Hardened scales make its weak attacks completely irrelevant
- DC 25 Nature: Digests food very slowly; swallowed prey isn’t quickly dissolved by acid, but usually dies because it is drained of its body heat, exhausting it
Combat
- Opens with Frost Shard Breath to devastate groups and alter the battlefield, or hinder prey from fleeing
- Tries to bite and swallow one or two targets while keeping others away with Tail attacks and its high movement speed, or simply shrugging off the damage thanks to its Impervious Scales
- Covers itself with its Ice Mist Breath to “digest” eaten creatures, obscure vision against range attacks, or gain advantage on its attacks thanks to its Blindsight
Loot Ideas
- Ancient weapons, armor, and other treasure preserved in permafrost and swallowed by it
- Scales, teeth, and bones are prized by crafters for resilient or cold immune magical items and objects
USING MONSTER VARIANTS
Monster variants allow the GM to adjust encounters to better match the party’s strength, narrative needs, or world-building logic. A weaker variant may represent a juvenile, wounded, or lesser specimen, while a stronger variant can serve as a leader, champion, ancient creature, or apex predator.
Variants can be used to fine-tune difficulty without changing the core identity of the monster, making them ideal for scaling encounters, reinforcing hierarchy within a faction, or creating memorable boss-style enemies. You can even use the same stat block but different variants in the same encounter if you want.
Design Note. Each monster is primarily balanced around its normal version. Weaker and stronger variants are derived adjustments and may not always preserve every tactical nuance or “feel” of the original creature. GMs are encouraged to review variants carefully and adjust abilities or tactics as needed to best suit their table.