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10 Awesome Monsters for a D&D 5e Swamp Encounter

Aquatic | Arctic | Cave or Underground | Desert | Forest | Grassland | Jungle | Mountain | Swamp

Are your adventurers heading into a swamp? Are they lost? Does your group need to find some monsters? Let us do the work for you. Here is a list of 10 Awesome Monsters for a Swamp Encounter from the recently released Dungeons & Dragons 5th Edition Monster Manual.

NOTE: Since this was first published in October 2014 the Dungeon Master Guide was released and provides lists of Monsters by Environment in Appendix B, but the lists are basic. In this article, you’ll find monsters that I think fit in a forest setting and some ideas on how to create encounters with each of them.

There are tons of monsters out there in all the books across versions, but this list includes only monsters that can be found in 5th Edition materials and would be typically found in a swamp. Let us know what’s your all-time favorite swamp monster in the comments below.

  1. Bullywug

    Challenge Rating: 1/4
    These frog-headed amphibious humanoids like to use superior numbers to overwhelm their prey. Deploy them in bulk as a challenge. Let your adventurers try to use intimidation and force the cowardly bullywugs to flee. Reward less powerful groups for catching a scout or using diplomacy when captured.

  2. Dragon, Black

    Challenge Rating: 2 to 21
    Black dragons love to see humanoid settlements collapse and could be placed in the crumbling ruins of a once proud civilization, now buried in a swamp. The evil-tempered black dragon stands out, even among other dragons, for its sadistic tenancies. Have a black dragon strike at the weakest of the adventurers, even offering mercy to only snatch it away.

  3. Giant Crocodile

    Challenge Rating: 5
    This beast can hold its breathe for 30 minutes, just long enough for you to wait before the croc attacks a group of adventurers too busy arguing about which way to turn in the endless swamp. With a +5 stealth and multiattack with bite and tail, facing even one crocodile could be too many.

  4. Green Hag

    Challenge Rating: 3
    While exploring a cave deep in a lonely swamp, the adventurers find a coven of hags. These monsters can be a challenging fight, but may offer interesting social encounter possibilities as an alternative. These hags reproduce by stealing human infants, so they could be the evil at the center of a mystery your adventurers fall into while visiting a bleak village at the edge of a moor.

  5. Hydra

    Challenge Rating: 8
    This reptilian horror with the body of a crocodile and multiple serpentine heads (that regrow when severed), could be found in the open swamp versus a lair. A hydra can serve as the beast at the end of a quest. If it worked for Hercules, why not for your adventurers.

  6. Lizardfolk

    Challenge Rating: 1/2 to 4
    These primitive reptilian humanoids could be found in the swamp patrolling outside their hut village or an ancient ruins. Lizardfolk are territorial and do not like outsiders, but they are not evil. They do what is needed to survive, including killing trespassing adventurers. You could also offer Lizardfolk as an race option for your players.

  7. Shambling Mound

    Challenge Rating: 5
    Shamblers trudge along consuming all organic matter in their path. Created by lightning, shamblers are reinvigorated by lightning and are not bothered much by fire or cold damage. Shamblers can be used to present a choice between fighting or choosing another path, since outrunning one is simplistic (Speed 20′).

  8. Stirge

    Challenge Rating: 1/2
    Stirges look like mosquito bats. Much like the mosquito, it has a long needle sticking out of its head to suck blood and uses feet to attach to its victim. A pack of stirges will be more than an annoyance for most parties, as more and more attach and continue to drain blood each round.

  9. Will-O’-Wisp

    Challenge Rating: 2
    Adventurers that chase one of these evil balls of light floating over a misty swamp can be lured into a trap such as quicksand, a monster lair or worse… if they are not killed by the wisp first. I included this originally in the forest encounter list, but it fits even better here.

  10. Yuan-Ti

    Challenge Rating: 1 to 7
    These serpent folk could be found by your adventurers in a remote temple, deep in a swamp. Yuan-ti range from being nearly human (pureblood) to snakes with arms (abomination). They are nearly emotionless and are skilled at exploiting emotions in others to get what they want.

Bonus Monsters & Beasts

  • Banshee
  • Blights
  • Constrictor Snake and Giant Constrictor Snake
  • Crocodile
  • Frog and Giant Frog
  • Giant Toad
  • Hydra
  • Lizard and Giant Lizard
  • Mud Mephit
  • Pixie
  • Poisonous Snake, Giant Poisonous Snake and Swarm of Poisonous Snakes
  • Sprite
  • Swarm of Insects
  • Treant

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