Merrow 5e: The Harpoon, the Pull and the Fight in the Water

A merrow is a CR 2 Large Monstrosity with AC 13, 45 hit points, a 40-foot swim speed and a 10-foot walking speed. It breathes air and water. Its signature attack is the harpoon: +6, 11 piercing damage, thrown up to 60 feet, and on a hit it drags the target toward itself, which usually means off the dock and into the water. In 2014 the target gets a Strength contest to resist a 20-foot pull. In 2024 there's no contest: the pull is 15 feet, and the merrow can harpoon twice in one turn.

Table of Contents

• •Merrow Stat Block (2014)
• •The Merrow in the 2024 Rules
• •How Merrows Fight
• •Running a Merrow Encounter
• •How Players Beat Merrows
• •Merrow Encounter Ideas
• •Frequently Asked Questions

Merrow Stat Block (2014)

The merrow from SRD 5.1:

The 2014 Multiattack is one bite plus either claws or the harpoon, so it harpoons at most once a turn. The harpoon works on a Huge or smaller creature, and the target resists with a Strength contest: the merrow rolls a Strength check at +4 against the target's Strength check. A fighter with Strength 16 is close to a coin flip; a wizard with Strength 8 gets pulled about seven times in ten.

Note the speeds. On land it moves 10 feet a turn, so it never leaves the water willingly. Everything in its kit is about bringing the fight to the edge of the water and then into it.

The Merrow in the 2024 Rules

SRD 5.2.1 keeps CR 2 (450 XP), AC 13, 45 hit points, Strength 18 and both speeds.

Two harpoon hits pull a 2024 target 30 feet in a single turn, with no roll to resist. That's enough to take a character standing 25 feet back from the rail of a ship and put them in the sea. The 2024 bite is weaker but leaves the target Poisoned, with Disadvantage on attack rolls and ability checks until the end of the merrow's next turn. That includes any Strength (Athletics) check the DM calls for to swim in rough water or climb back onto the dock.

The 2024 merrow makes two Harpoon attacks a turn, but the stat block doesn't say how it gets the harpoon back. Give it a line on the harpoon, or two harpoons, and decide before the fight.

How Merrows Fight

Pull first, bite second. A 2014 merrow should throw the harpoon before it bites. If the harpoon hits a target 20 feet away and wins the contest, the target lands next to the merrow, and the bite (8 damage) follows the same turn. A 2024 merrow throws twice and, if the second throw brings the target within 5 feet, bites on its next turn and poisons it.

Expected damage per round against AC 16 (the merrow hits on a 10 or higher, 55%):

The numbers are modest for CR 2. The danger is where the damage happens: in the water.

Underwater, the party fights at a penalty. Once a character is in the water, the underwater combat rules apply.

• •2014: a creature without a swimming speed has Disadvantage on melee weapon attacks unless the weapon is a dagger, javelin, shortsword, spear or trident. Ranged weapon attacks automatically miss beyond normal range and have Disadvantage within it, unless the weapon is a crossbow, a net or a thrown weapon like a javelin, spear, trident or dart.
• •2024: a creature without a Swim Speed has Disadvantage on melee weapon attacks unless the weapon deals Piercing damage. Ranged weapon attacks automatically miss beyond normal range and have Disadvantage within it.
• •Both: anything fully underwater has Resistance to fire damage, and swimming without a swim speed costs an extra foot of movement per foot.

A fighter with a longsword in the water attacks at Disadvantage. The merrow, with a swim speed, doesn't.

Stay low, stay close to the edge. A merrow in the water next to a dock has the dock between it and anyone above. Have it surface, throw, and sink. At 10 feet of walking speed, it never climbs onto the dock.

Retreat. At around 15 hit points, it swims off at 40 feet a round. Nobody without a swim speed follows.

Running a Merrow Encounter

A merrow is 450 XP. With the 2024 XP budget per character (SRD 5.2.1), for four characters:

Under the 2014 Dungeon Master's Guide guidelines (used by our encounter calculator), one merrow is a Medium encounter for four level 2 characters.

Terrain decides the difficulty more than the XP. The same merrow plays like an easy fight on a sandy beach where the party can back away from the water, and close to deadly on a narrow pier at night with a party in chain mail. In both editions a character can hold its breath for 1 + its Constitution modifier minutes (minimum 30 seconds), so drowning takes a while, but every round in the water is a round at Disadvantage.

How Players Beat Merrows

• •Stand back from the edge. A 2014 merrow pulls 20 feet per turn; a 2024 merrow, 30. Standing more than 20 feet from it also puts you in its harpoon's long range (21 to 60 feet), where its throws have Disadvantage.
• •Use the right weapons. Spears, javelins, daggers, shortswords and tridents (2014) or any piercing weapon (2024) work underwater without Disadvantage. A rogue with a rapier is fine in 2024 and penalized in 2014.
• •Win the contest in 2014. The pull is a Strength contest. Characters with high Strength go to the front; the wizard stands at the back.
• •Hit it when it surfaces. It has AC 13 and 45 hit points. Ready an attack for the moment it rises to throw. Lightning Bolt or Guiding Bolt aren't affected by the underwater fire resistance; fire spells against a submerged merrow deal half damage.
• •Don't spend a spell on the 2024 poison. The Poisoned condition from its bite lasts only until the end of the merrow's next turn. Moving out of its reach does more good than a cure.

Merrow Encounter Ideas

The night pier. Three fishermen have vanished from the end of the same pier in a month. The harbormaster says they got drunk and fell in. A merrow sleeps under the pier boards and waits for anyone who sits at the end with a lantern. The party can bait it with a lit lantern and a dummy, or someone can volunteer.

The cable ferry. A flat ferry crosses a flood-swollen river on a rope. Two merrows have learned to wait halfway, where the river is deepest. They harpoon passengers off the raft, one per turn. If the party cuts the merrows' line or kills one, the other cuts the ferry rope.

The shrine below the tide. At low tide a flight of stairs leads down to a flooded chapel where merrows pray in Abyssal to something. The party has the length of the tide, about six hours, to get in and out. Inside, every fight is underwater.

Frequently Asked Questions

What CR is a merrow in 5e?

A merrow is CR 2 and worth 450 XP in both the 2014 and 2024 rules. It has AC 13, 45 hit points, a 10-foot walking speed and a 40-foot swim speed.

How does the merrow's harpoon work?

It's a melee or ranged attack (+6, reach 5 feet or range 20/60 feet) that deals 11 (2d6 + 4) piercing damage. In 2014 a Huge or smaller target that loses a Strength contest is pulled up to 20 feet toward the merrow. In 2024 a Large or smaller target is pulled up to 15 feet with no contest, and the merrow can harpoon twice a turn.

Can a merrow breathe out of water?

Yes. Its Amphibious trait lets it breathe air and water, but its 10-foot walking speed keeps it near the shore.

What's the difference between a merrow and a merfolk?

A merfolk is a CR 1/8 Medium creature with a spear and 11 hit points (a Humanoid in 2014; the 2024 Merfolk Skirmisher is an Elemental). A merrow is a CR 2 Large Monstrosity with 45 hit points, a harpoon that drags victims into the water, and a bite and claws. Loreify can record the session and keep a list of the creatures and NPCs the party met at sea: see the D&D note-taking app.

Stat blocks: System Reference Document 5.1 (2014) and 5.2.1 (2024), Wizards of the Coast, CC-BY-4.0. Tactics, encounter math and ideas are Loreify's own.