Arena of the Labors

Six labors reborn on sacred sand — without the hero who first won them.

Style: Stadium · 6 waves · reuses Hydra / Stymphalian / Boar centerpieces · no Heracles
Win: Clear six labors (capture/pen OK)
Lose: Dragged out or Chant Clock 3
QG: Melanthios · Ally: Thaleia · Maguffin: Olive-Resin Club

"Not the hero's name — the sand's…"

Waves

Nemean Lion — hide / pin
Lernaean Hydra — heads + fire (tracker)
Mares of Diomedes — recruit Thaleia
Stymphalian Birds — thunder / nets
Erymanthian Boar — capture preferred
Cretan Bull — Hard · stake club

Difficulty

Tier	Adjust
Easier	3-head hydra; fewer mares/birds; rest before Gate III
As Written ★	6×L8
Harder	Overlap Bull with Boar still up

Through Misthaven mist into Archon Melanthios 's Labor Games. The demigod who first beat these monsters is not present and must not be summoned. Six gates: Nemean Lion → Lernaean Hydra → Mares of Diomedes → Stymphalian Birds → Erymanthian Boar → Cretan Bull . Hydra, birds, and boar intentionally echo other library set pieces — staged here as arena waves.

Creature / Enemy List

Creature	Counts / Notes
Nemean Lion	1 · 1 · Wave 1 · Labor I
Lernaean Hydra	1 · 1 · Wave 2 · Labor II · heads
Mare of Diomedes	2 · 3 · 4 · Wave 3 · Labor VIII
Bronze-Beaked Stymphalian	4 · 6 · 8 · Wave 4 · Labor VI
Erymanthian Boar	1 · 1 · Wave 5 · Labor IV
Cretan Bull	1 · Wave 6 Hard · Labor VII
Stadium Gate-Hoplite	0–2 · 2–4 · Optional
Thaleia of the Bit	1 · 1 · Recruit Enc. 2

DM Tips

As Written ★ — 6 Players, Average Level 8: Lion → Hydra (5 heads) → 3 mares → 6 Stymphalians → Boar → Cretan Bull. Short rest only before Gate II.
Easier: Hydra starts at 3 heads / no double-regrow. 2 mares; 4 birds. Boar HP 120. Bull HP 160, no Pivot Charge. Short rest before Gate III.
Harder: Hydra max 10 heads. 4 mares; 8 birds. Bull enters while Boar still at 25% HP.

Encounter 1 — Gate I: Lion & Hydra

🗺 Terrain Stadium floor · 80×80 ft sand · 10-ft wall · four gates · two sand-pit traps (DC 14 Dex or prone) · braziers at each gate (lit; fire for cauterize) · mural ring of the Twelve Labors. · Two waves, 2–3 minute gate-reset (no short rest). Nemean Lion first, then the Lernaean Hydra — same multi-head puzzle the library uses elsewhere, compressed for the sand.

Win: 0 HP, pin (3× Athletics DC 16 after bloodied), or drive through North gate.
Hide ignores mundane non-bludgeoning; Olive-Resin Club ignores once/encounter.
Chant Clock: hush demigod-name shouts (Intimidation/Persuasion DC 14).
Start 5 heads . Sever on 25+ damage hit (or called shot). Multiattack = number of heads.
Cauterize stump with fire/acid same round (torch from brazier, spell, or club + flame) or it regrows two heads at end of hydra's turn (max 8).
Win at 0 heads or 0 HP after final head. Handlers flood the sand if the fight exceeds ~8 rounds.

Encounter 2 — Gate II: Mares & Stymphalians

Short rest (~10 min) before Gate II. Mares from the East chute; then a Stymphalian flock from the open sky (same bronze-beak threat as Stymphalian Storm ). Thaleia is chained at the bit-rack during Wave 3.

3 mares (Hard: 4). Free Thaleia to recruit (or vow to pen, not slaughter).
Skill path: drive 3 through West gate (shove / lariat / Animal Handling DC 16).
Mare reaches stands → Chant Clock +1.
As written: 6 birds (Easy 4 / Hard 8). Flyby + Dive Bomb. Thunder/gongs impose disadvantage.
Skill path: 4 successes before 3 failures (Performance, Athletics gongs, Survival herding, Arcana weather DC 15) drives the flock into the West pen netting — ends the wave with half the remaining birds captured.
Thaleia nets: Ready vs dive. Combat win: reduce flock to ≤2 or force a scatter (all bloodied + one gong success).
Tip: Medium Humanoid (human), Neutral Good · Recruitable Ally · Stablewright
Tip: RECRUITMENT (Enc. 2). Free her from the bronze bit-rack before any mare is killed, or promise the mares will be driven to the holding pens rather than slaughtered for the crowd.

Encounter 3 — Gate III: Boar & Bull (Boss)

Tusk Sweep (Recharge 5–6). Each creature within 10 ft. DC 16 Dex save or 18 (4d8) slashing and prone. · Water and a cheer only — no full rest. Erymanthian Boar (Calydon-scale quarry energy, capture-preferred labor) then the Cretan Bull Hard finale.

Charge + Relentless. Preferred win: capture/pen while bloodied (3× Athletics/Animal Handling DC 16 + portcullis).
Club: once, brief plant → advantage on next shove/grapple vs boar.
If the boar fight exceeds 5 rounds, Melanthios may release the Bull early (overlap — brutal).
Legendary actions. Charge / Sandstorm Bellow / Earth-Shatter Hooves.
WIN — MAGUFFIN: Plant Olive-Resin Club (action, DC 14). Next charge hits stake or 4d10 + prone.
Pen track while bloodied, or slay. Chant Clock 3: bull heals 40 once + extra legendary that round.
Portcullis or 0 HP → mortal olive crown; murals of the absent hero look away.
Tip: Medium Humanoid (human), Neutral Good · Recruitable Ally · Stablewright

DM Callouts

Medium Humanoid (human), Neutral Good · Recruitable Ally · Stablewright
RECRUITMENT (Enc. 2). Free her from the bronze bit-rack before any mare is killed, or promise the mares will be driven to the holding pens rather than slaughtered for the crowd.
Horse-Sense. While recruited, allies within 10 ft. have advantage on saves against the mares' Panic Whinny and on Animal Handling checks to drive the Erymanthian Boar.
Medium Humanoid (human), Neutral Good · Recruitable Ally · Stablewright

STAT BLOCKS

Thaleia of the Bit

Medium Humanoid (human), Neutral Good · Recruitable Ally · Stablewright

AC 15 | HP 72 | Speed 30 ft.

	STR	DEX	CON	INT	WIS	CHA
sc md sv	14 +2 +2	14 +2 +2	14 +2 +2	12 +1 +1	15 +2 +2	13 +1 +1

RECRUITMENT (Enc. 2). Free her from the bronze bit-rack before any mare is killed, or promise the mares will be driven to the holding pens rather than slaughtered for the crowd.

Horse-Sense. While recruited, allies within 10 ft. have advantage on saves against the mares' Panic Whinny and on Animal Handling checks to drive the Erymanthian Boar.

Net Hand. Carries 2 hunting nets. Can Ready a net against a diving Stymphalian (DC 14 Str save or restrained).

Lariat Whip. Melee Weapon Attack: +6 to hit, reach 10 ft., one target. Hit: 9 (2d4 + 4) slashing. On a hit against a Mare of Diomedes, the mare is restrained until end of Thaleia's next turn (escape DC…

Nemean Lion (Arena Echo) CR 6

Large Beast · Wave 1 · Labor I

AC 17 | HP 136 | Speed 50 ft.

	STR	DEX	CON	INT	WIS	CHA
sc md sv	20 +5 +5	15 +2 +2	18 +4 +4	4 −3 −3	14 +2 +2	10 +0 +0

Hide That Will Not Cut. Immune to damage from nonmagical attacks that aren't bludgeoning. Magical piercing/slashing deals half. Bludgeoning, force, and the Olive-Resin Club ignore this trait.

Pounce. If the lion moves at least 20 ft. straight toward a creature and hits with a claw, the target must succeed on a DC 16 Strength save or be knocked prone. Bite as a bonus action.

Arena Echo. Slayable labor-echo. Same iconic threat as other lion hunts in the library — Heracles is not present.

Attack. Bite +9 to hit, 16 (2d10 + 5) piercing plus 7 (2d6) thunderous roar damage, or Claw +9 to hit, 14 (2d8 + 5) slashing. Multiattack: two claws or one bite.

Lernaean Hydra (Arena Echo) CR 8

Huge Monstrosity · Wave 2 · Labor II · Library centerpiece

AC 15 | HP 172 | Speed 30 ft., swim 30 ft.

	STR	DEX	CON	INT	WIS	CHA
sc md sv	20 +5 +5	12 +1 +1	20 +5 +5	2 −4 −4	10 +0 +0	7 −2 −2

Multiple Heads. While it has more than one head, advantage on saves vs. blinded, deafened, stunned, and charmed. Sever a head when a single hit deals 25+ damage, or a called shot after bloodied (DM fiat).…

Reactive Heads. One reaction per head — usually opportunity attacks.

Wakeful. While it has at least 2 heads, it cannot be surprised.

Regrow (unless cauterized). At the end of its turn, if a head was severed since its last turn and the stump was not dealt fire or acid damage (or a club cauterizing strike), it grows two heads (max 8). Same gimmick…

Mare of Diomedes CR 4

Large Beast · Wave 3 · Labor VIII

AC 14 | HP 76 | Speed 60 ft.

	STR	DEX	CON	INT	WIS	CHA
sc md sv	18 +4 +4	14 +2 +2	16 +3 +3	3 −4 −4	12 +1 +1	7 −2 −2

Pack Hunger. Advantage on attacks against a creature if another Mare is within 5 ft. of it.

Panic Whinny. When a Mare drops to 0 HP, each other Mare within 30 ft. can use a reaction to move half Speed without provoking, or make one bite against a creature that damaged the fallen mare.

Attack. Bite +7 to hit, 13 (2d8 + 4) piercing plus 5 (1d10) necrotic. Target creature: mare regains 5 HP.

Trample. Move up to Speed through enemy spaces (Medium or smaller). DC 15 Str/Dex save or 11 (2d6 + 4) bludgeoning and prone.

Session reminders

Lion — AC 17 / 136
Hydra — AC 15 / 172 · 5 heads
Mare — AC 14 / 76
Stymphalian — AC 15 / 45 · flyby
Boar — AC 17 / 168
Bull — AC 18 / 210 · legendaries

Maguffin

Olive-Resin Club

Ignore lion hide; cauterize hydra stump with flame
Boar grapple adv; Bull stake redirect

STAT BLOCKS (cont.)

Bronze-Beaked Stymphalian CR 3

Medium Monstrosity · Wave 4 flock · Labor VI · Library centerpiece

AC 15 | HP 45 | Speed 10 ft., fly 60 ft.

	STR	DEX	CON	INT	WIS	CHA
sc md sv	12 +1 +1	16 +3 +3	14 +2 +2	4 −3 −3	12 +1 +1	7 −2 −2

Flyby. Does not provoke opportunity attacks when it flies out of reach.

Bronze Plumage. Resistance to nonmagical slashing. Thunder or loud noise: disadvantage on attacks until end of its next turn.

Flock Tactics. Advantage on attacks if another Stymphalian is within 10 ft. of the target. Same bird threat as Stymphalian Storm — staged here as an arena wave.

Attack. Bronze Beak +6 to hit, 10 (2d6 + 3) piercing, or Razor Feather +6 to hit, range 60/120 ft., 8 (1d10 + 3) slashing.

Erymanthian Boar (Arena Echo) CR 8

Large Beast · Wave 5 · Labor IV · Library centerpiece kin

AC 17 | HP 168 | Speed 40 ft.

	STR	DEX	CON	INT	WIS	CHA
sc md sv	20 +5 +5	12 +1 +1	18 +4 +4	3 −4 −4	12 +1 +1	7 −2 −2

Charge. If it moves ≥20 ft. straight then hits with gore, +13 (3d8) piercing and DC 16 Str save or pushed 15 ft. and prone.

Relentless (1/day). If reduced to 0 HP by an attack dealing ≤30 damage, drops to 1 HP instead.

Capture Labor. Mythic labor was capture alive. Preferred win: restrain / net / pen while bloodied (3 Athletics or Animal Handling DC 16) then drop the North portcullis. Same big-boar energy as Calydon —…

Arena Echo. Heracles absent. Slayable if the crowd demands blood.

Cretan Bull (Arena Echo) CR 9

Huge Beast · Wave 6 boss · Hard · Labor VII

AC 18 | HP 210 | Speed 50 ft.

	STR	DEX	CON	INT	WIS	CHA
sc md sv	22 +6 +10	12 +1 +1	20 +5 +9	3 −4 −4	12 +1 +1	9 −1 −1

Siege Beast. Double damage to objects and structures.

Charge. If it moves ≥20 ft. straight then hits with gore, +18 (4d8) piercing and DC 18 Str save or pushed 15 ft. and prone.

Earth-Shatter Hooves. Sand within 10 ft. is difficult terrain for others.

No Demigod. Win: 0 HP, pen while bloodied (3× Athletics/Animal Handling DC 16 + portcullis), or club-stake setup. Heracles does not appear.

Stadium Gate-Hoplite CR 2

Medium Humanoid · Optional reinforcement

AC 16 | HP 45 | Speed 30 ft.

	STR	DEX	CON	INT	WIS	CHA
sc md sv	14 +2 +2	12 +1 +1	14 +2 +2	10 +0 +0	11 +0 +0	10 +0 +0

Crowd Control. Open pens / shield walls on Melanthios's order. Enter sand only if a beast breaches the stands.

Attack. Spear +5 to hit, 7 (1d8 + 3) piercing, or Shield Bash +5 to hit, 6 (1d6 + 3) bludgeoning and DC 13 Str save or prone.

NPC / ALLY

Archon Melanthios

No naming Heracles · Chant Clock

Thaleia of the Bit

Recruit during mares · lariat / nets

Remember

Heracles never appears. Labors I, II, VIII, VI, IV, VII.
Hydra / birds / boar may echo other Theronauts guides — fine to reuse.

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