Rules edition: This build pairs the legacy Grung from One Grung Above with the 2014 Barbarian. Grung is optional supplemental material and needs your DM’s approval. Tasha’s optional origin rule can reassign the Grung’s ability increases if your DM allows it. This guide does not use the revised 2024 Barbarian or species rules.
A Grung Barbarian is a mobile, durable character with a poison trait that rewards contact and careful positioning. The build’s limits are real: Strength receives no default increase, poison-resistant enemies blunt some of your signature options, and daily water immersion matters. Build around those facts instead of treating Poisonous Skin as automatic damage.
What the Grung traits actually do
The legacy Grung is Small, has a 25-foot walking speed and climbing speed, can breathe air and water, and is immune to poison damage and the Poisoned condition. Arboreal Alertness grants Perception proficiency and advantage on initiative rolls. Standing Leap allows a long jump of up to 25 feet and a high jump of up to 15 feet, with or without a running start.
Poisonous Skin has two separate uses: a creature that grapples you or otherwise directly touches your skin makes a fixed DC 12 Constitution save or becomes Poisoned for 1 minute. When it is no longer in direct contact with you, it can repeat the save at the end of each of its turns. Separately, as part of an attack with a piercing weapon, you can apply the poison to that weapon; a hit forces a DC 12 Constitution save or deals 2d4 poison damage. The contact effect does not deal 2d4 damage, and the weapon effect does not inflict the Poisoned condition. Neither save DC scales with your Constitution or proficiency bonus.
Water Dependency requires at least 1 hour of immersion each day. If you miss it, you gain 1 level of Exhaustion at the end of that day. The trait says this Exhaustion can be removed only by magic or by immersing for at least 1 hour. Plan the rest and travel routine with your DM, especially in dry or dungeon-heavy adventures.
Ability scores, weapons, and defenses
Strength is still the simplest Barbarian attack stat. The legacy Grung’s fixed increases are +2 Dexterity and +1 Constitution, not Strength. With standard array, one starting spread is Strength 15, Dexterity 14 (16 after the Grung increase), Constitution 13 (14 after the increase), Wisdom 12, Charisma 10, and Intelligence 8. If your table uses Tasha’s optional origin rule, ask whether you can reassign the increases; do not assume they move automatically.
Small size does not reduce your weapon damage dice or carrying capacity by itself. Under the 2014 rules, it gives you disadvantage on attack rolls with weapons that have the Heavy property, so choose a non-Heavy weapon such as a longsword, battleaxe, warhammer, spear, or rapier. A Barbarian can use Strength with a finesse weapon, so a rapier remains compatible with Rage. Rage adds damage to melee weapon attacks made using Strength and grants resistance to bludgeoning, piercing, and slashing damage; it does not make attacks against you harder to hit and does not resist poison.
Use medium armor if it gives you better AC than Unarmored Defense (10 + Dexterity modifier + Constitution modifier). A shield is an option with a one-handed weapon. Your d12 Hit Die is the same as any other Barbarian’s; Small size does not make you more fragile.
Subclass and combat plan
Choose a subclass for the role you want. Path of the Beast supports a feral theme and gives you natural weapon options while raging; its claws can grant one additional claw attack as part of the Attack action on your turn, not as a bonus action. Ancestral Guardian emphasizes protecting allies, while Totem Warrior offers defensive or mobility choices. These subclass features come from their own sourcebooks, so confirm your table allows them.
Use your climb speed and jumps to reach useful lanes, cross gaps, or reposition around obstacles. Standing Leap is movement, not teleportation: respect landing space, jump distance rules, and any movement you have left. When a foe is likely to grapple you or make direct skin contact, Poisonous Skin can impose the Poisoned condition after a failed save; that can hinder its attacks and ability checks. Do not expect it to trigger just because an enemy hits you with an ordinary weapon attack.
Your piercing-weapon poison costs no bonus action, but it applies as part of an attack and only deals its 2d4 poison damage on a failed save. It is useful when poison matters and less reliable against creatures with strong Constitution saves, poison resistance, or poison immunity. Keep a dependable weapon and your normal Rage damage plan; the Grung trait is an option, not your whole damage engine.
Party logistics and roleplay
Tell the party how direct skin contact works and agree on practical ways to handle routine care. The trait affects a creature that directly touches your skin; it does not make every ally who stands nearby take damage. Gloves or other coverings can help avoid casual contact if the DM agrees they prevent it, but clarify how your table handles armor, grapples, and urgent healing before play.
Water Dependency is a shared travel consideration, not a reason to assume the character is unplayable. A waterskin is not automatically enough for an hour of immersion. Ask what water sources, rest opportunities, and consequences your DM expects. Grung can speak, read, and write Grung; establish how your character communicates if the party does not share the language.
Is this build right for your campaign?
This build fits a campaign that allows Grung and gives the group room to manage its water requirement. Its strongest contributions are Barbarian durability, vertical mobility, initiative advantage, and conditional poison control. If your campaign features many poison-immune foes or offers no practical way to meet the daily immersion requirement, ask the DM before choosing it. Otherwise, build for Strength, choose a non-Heavy weapon, and use Poisonous Skin when its actual trigger occurs.
Official Rules Sources
- One Grung Above on D&D Beyond — the Grung rules supplement; ask your DM whether it is allowed.
- D&D Beyond species listing — identifies the Grung trait names and legacy ability increases.
- 2014 Player’s Handbook — Barbarian, ability scores, Small size, jumping, weapons, and Exhaustion rules.
- Tasha’s Cauldron of Everything — optional origin customization, only if the DM permits it.
