Monster Analysis: Sea Spawn

Thanks to @mourningcrows for this art piece!

  • Armor Class 11

  • Speed 20 ft, Swim 30 ft

  • Darkvision 120 ft, Passive 10

  • Suggested Average, Max HP: 32, 50

    • Sea Spawn 1: 45 damage taken, killing blow by Fjord, Caleb, and Caduceus

    • Sea Spawn 2: 46 damage taken, 27 killing blow by Nott

    • Sea Spawn 3: 39 damage taken , 8 killing blow by Nott

    • Sea Spawn 4: 36 damage taken, 6 killing blow by Beau

    • Sea Spawn 5: 58 damage taken, 34 killing blow by Caleb and Jester

Sea Spawn are created from beings that find themselves in over their heads (heh) in the ocean, but have their lives spared by creatures that live below… but not for the benefit of the drowned. As Caduceus discovered, sea spawn aren’t undead because they were never allowed to die. These individuals are transformed into sea spawn, humanoids with a variety of aquatic mutations, cursed to live out their existence underwater at the behest of a greater being.

Sea Spawn are incredibly easy to hit, especially for level seven adventurers like The Mighty Nein. What they have going in their favor is their swim speed, 30 ft, and their melee multi-attacks. The sea spawn the Nein battled had stronger attacks than those in Volo’s, and each had its own piscine anatomy attack. Two of them demonstrated tentacle attacks, and at least one had a poison quill attack.

The Mighty Nein really benefited from three tactical decisions. First, they positioned themselves so that they were separated with the melee attackers in front, but no one was totally alone. This forced the sea spawn to spread out, preventing them from ganging up on any one person. Second, the Nein took out the sentinel sea spawn in one fell swoop, using their element of surprise to the full effect. This gave the party an entire round to fire on the remaining spawn and prepare attacks with shorter ranges without being harried. Third, the Nein forced the spawn to come to them.

While the spawn have a quicker swim speed than all but Fjord, sea spawn have no ranged attacks at their disposal, giving the Nein’s ranged combatants an extra round to harry the defenders as they approached. Caleb fired Magic Missiles and cast Haste on Fjord, who Eldritch Blasted; Nott fired her hand crossbow; Jester shot a Guiding Bolt and Tolled the Dead; and Caduceus landed a Sacred Flame. Additionally, Caduceus largely set the tempo of the encounter. His Bane ensured Beau was impossible to hit, and his Sentinel at Death’s Door ability reduced a critical hit on Yasha to a regular one, ensuring that she dealt nearly three times as much damage as she absorbed.

The sea spawn, though not a particularly difficult challenge, gave The Mighty Nein a preview of what lies in wait at the second temple of Uk’otoa. While the first temple presented themes and variations on snakes ( thanks to the temple’s overtaking by the Zehir-worshipping yuan-ti), this second temple’s denizens lean significantly more underwater tentacle-based aberrations. The spawn also gave Fjord a body to use to scout into the temple without any party members taking damage from the revealed chuul inside. It remains to be seen if the chuul the Nein witnessed are the last guardians of this temple, or if something bigger and more dangerous lies beneath.