5e SRD >Creatures >


Medium plant, neutral

Armor Class 14
Hit Points 45 (6d8 + 18)
Speed 20 ft.

19 (+4) 10 (+0) 16 (+3) 4 (-3) 10 (+0) 10 (+0)

Saving Throws Constitution +5
Skills Stealth +4
Damage Resistances slashing and piercing damage from nonmagical attacks
Damage Immunities lightning and fire damage
Condition Immunities prone
Senses darkvision 60 ft., tremorsense 120 ft., passive Perception 10
Languages Common (understands but can’t speak)
Challenge 3 (700 XP)

Special Traits

  • Animate Trees. An algoid can innately cast the animate objects spell at will, requiring no components. Each casting animates two trees, which are all the algoid can control at a time. A newly-animated tree takes one full round to uproot itself. Once free, trees act on the algoid’s turn.
  • Vulnerability to Water Magic. Control water and create or destroy water spells deal 10 (3d6) piercing damage to an algoid.
  • Water Camouflage. An algoid has advantage on Stealth checks when it is in or on standing water.


  • Multiattack. The algoid makes two Slam attacks.
  • Slam. Melee Weapon Attack: +6 to hit, reach 5 ft., one creature. Hit: 8 (1d8 + 4) bludgeoning damage. If an algoid scores a critical hit with this attack, the target must make a successful DC 17 Constitution saving throw or be stunned. The stunned creature can repeat the saving throw at the end of each of its turns; the condition ends on a successful save.
  • Mind Blast. Any creature within a 60 ft. cone must succeed on a DC 13 Intelligence saving throw or be stunned for 3d4 rounds.


The algoid is a living colony of algae that has developed some semblance of intelligence and mobility. It is roughly humanoid in shape and resembles a green humanoid. Algoids make their lairs in marshes and swamps. They are often encountered with other marsh-dwelling sentient plants; though never with shambling mounds (they hate them and usually attack them on sight). The algoid is 7 feet tall and weighs about 300 pounds. In its natural surroundings, it is nearly invisible until it attacks and uses this to its advantage when prey is nearby. The “skin” of an algoid is coarse and rough with a leafy texture. The algoid often lies in wait, partially submerged in water or a bog, until its prey passes nearby. It springs to attack with its powerful fists when its opponents come within range.

Section 15: Copyright Notice
City of Brass ©2018 Frog God Games; Authors: Casey Christofferson and Scott Greene