Sludge Crawler
Medium • Ooze • Unaligned
Armor Class 11
Hit Points 66 (12d8 + 12)
Speed 30 ft., climb 20 ft.
Initiative +1 (11)
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 15 (+2) | 12 (+1) | 14 (+2) | 6 (-2) | 10 (+0) | 6 (-2) |
Saving Throws Con +4
Skills Athletics +4, Stealth +3
Damage Immunities acid, poison
Condition Immunities deafened, exhaustion, grappled, poisoned, prone
Senses blindsight 10 ft., darkvision 60 ft., passive Perception 10
Languages understands Common but can’t speak
CR 4 (XP 1,100; PB +2)
Amorphous. The sludge crawler can move through a space as narrow as 1 inch wide without squeezing.
Amplified Strain. A creature that contracts the sewer’s plague through a sludge crawler has disadvantage on all saving throws against the disease. Further, when a creature dies while it has contracted the disease, its body liquifies and turns into a slime crawler. The liquefaction happens immediately if the creature dies because of the disease. Otherwise, it happens over a duration of 24 hours.
Spider Climb. The sludge crawler can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.
Unusual Nature. The sludge crawler doesn't require air or sleep.
ACTIONS
Multiattack. The sludge crawler makes up to three Slam attacks. It can replace one of these attacks with a use of Fling Arm.
Slam. Melee Weapon Attack: +4, reach 5 ft. Hit: 5 (1d6 + 2) bludgeoning damage plus 7 (2d6) poison damage, and the target becomes poisoned until the end of its next turn. If the target is already poisoned, Constitution Saving Throw: DC 12. Failure: The target contracts the sewer’s plague disease.
Fling Arm (2/Day). Dexterity Saving Throw: DC 12, one creature within 30 feet of the sludge crawler that it can see. Failure: 15 (3d8 + 2) bludgeoning damage, and the target is knocked prone and restrained (escape DC 12). Failure or Success: The sludge crawler makes cumulatively one Slam attack less as part of its Multiattack until it finishes a long rest.
Sludge Crawler
Medium • Ooze • Unaligned
Armor Class 10
Hit Points 27 (5d8 + 5)
Speed 30 ft., climb 20 ft.
Initiative +0 (10)
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 13 (+1) | 10 (+0) | 12 (+1) | 6 (-2) | 10 (+0) | 6 (-2) |
Skills Athletics +3, Stealth +2
Damage Immunities acid, poison
Condition Immunities deafened, exhaustion, grappled, poisoned, prone
Senses blindsight 10 ft., darkvision 60 ft., passive Perception 10
Languages understands Common but can’t speak
CR 1 (XP 200; PB +2)
Amorphous. The sludge crawler can move through a space as narrow as 1 inch wide without squeezing.
Amplified Strain. A creature that contracts the sewer’s plague through a sludge crawler has disadvantage on all saving throws against the disease. Further, when a creature dies while it has contracted the disease, its body liquifies and turns into a slime crawler. The liquefaction happens immediately if the creature dies because of the disease. Otherwise, it happens over a duration of 24 hours.
Spider Climb. The sludge crawler can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.
Unusual Nature. The sludge crawler doesn't require air or sleep.
ACTIONS
Multiattack. The sludge crawler makes up to two Slam attacks. It can replace one of these attacks with a use of Fling Arm.
Slam. Melee Weapon Attack: +3, reach 5 ft. Hit: 5 (1d6 + 1) bludgeoning damage plus 3 (1d6) poison damage, and the target becomes poisoned until the end of its next turn. If the target is already poisoned, Constitution Saving Throw: DC 11. Failure: The target contracts the sewer’s plague disease.
Fling Arm (1/Day). Dexterity Saving Throw: DC 11, one creature within 30 feet of the sludge crawler that it can see. Failure: 10 (2d8 + 1) bludgeoning damage, and the target is knocked prone and restrained (escape DC 11). Failure or Success: The sludge crawler makes one Slam attack less as part of its Multiattack until it finishes a long rest.
Sludge Crawler
Medium • Ooze • Unaligned
Armor Class 12
Hit Points 90 (12d8 + 36)
Speed 30 ft., climb 30 ft.
Initiative +2 (12)
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 17 (+3) | 14 (+2) | 16 (+3) | 6 (-2) | 10 (+0) | 6 (-2) |
Saving Throws Str +6, Con +6
Skills Athletics +6, Stealth +5
Damage Immunities acid, poison
Condition Immunities deafened, exhaustion, grappled, poisoned, prone
Senses blindsight 30 ft., darkvision 60 ft., passive Perception 10
Languages understands Common but can’t speak
CR 7 (XP 2,900; PB +3)
Amorphous. The sludge crawler can move through a space as narrow as 1 inch wide without squeezing.
Amplified Strain. A creature that contracts the sewer’s plague through a sludge crawler has disadvantage on all saving throws against the disease. Further, when a creature dies while it has contracted the disease, its body liquifies and turns into a slime crawler. The liquefaction happens immediately if the creature dies because of the disease. Otherwise, it happens over a duration of 24 hours.
Spider Climb. The sludge crawler can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.
Unusual Nature. The sludge crawler doesn't require air or sleep.
ACTIONS
Multiattack. The sludge crawler makes up to four Slam attacks. It can replace one of these attacks with a use of Fling Arm.
Slam. Melee Weapon Attack: +6, reach 5 ft. Hit: 6 (1d6 + 3) bludgeoning damage plus 7 (2d6) poison damage, and the target becomes poisoned until the end of its next turn. If the target is already poisoned, Constitution Saving Throw: DC 14. Failure: The target contracts the sewer’s plague disease.
Fling Arm (3/Day). Dexterity Saving Throw: DC 14, one creature within 30 feet of the sludge crawler that it can see. Failure: 21 (4d8 + 3) bludgeoning damage, and the target is knocked prone and restrained (escape DC 14). Failure or Success: The sludge crawler makes cumulatively one Slam attack less as part of its Multiattack until it finishes a long rest.
QUICK REFERENCE
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.