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Witcher 3: Wild Hunt – RemasteredUnderdocks
The Underdocks is the alternate first act of Slay the Spire 2, a sewer waterway chosen by a coin flip against the Overgrowth once unlocked, with the Elites Phantasmal Gardener, Skulking Colony and Terror Eel and the bosses Lagavulin Matriarch, Soul Fysh and Waterfall Giant.
The Underdocks is the alternate first act of Slay the Spire 2, which Mega Crit describes as "a miry waterway connected to the Spire's sewer system" full of mutant sea creatures and vagrants; its Elites are the Phantasmal Gardeners, the Skulking Colony and the Terror Eel, and its boss is the Lagavulin Matriarch, Soul Fysh or Waterfall Giant. Once it is unlocked, every run flips a coin after Neow: Mega Crit's Major Update #2 notes say a generated decimal below 0.5 gives the Overgrowth and anything else the Underdocks. The game is in Early Access, and several of this act's fights were reworked in its first months.
Quick facts
| Act | Act 1, one of two (the other is the Overgrowth) |
| Chance | A coin flip, 50%, once unlocked, per Mega Crit (Jun 19, 2026) |
| Unlock | An Epoch named "Underdocks" on the Timeline, per Destructoid |
| Elites | Phantasmal Gardener, Skulking Colony, Terror Eel |
| Bosses | Lagavulin Matriarch, Soul Fysh, Waterfall Giant (one per run, shown on the map) |
| Events | 9 of its own, plus the shared pool |
| Next | Act 2, the Hive |
| Version | Main branch v0.107.1; numbers below are OP.GG's data from the public beta v0.111.0 unless marked |
What the Underdocks is
The Underdocks is a flooded sewer under the Spire and the second of the two Act 1s. Mega Crit revealed it in its September 2025 Neowsletter together with the Overgrowth, saying the two acts "differ radically in their environments, enemies, events, and bosses", and teased the Terror Eel as one of its inhabitants. Its two-tailed rat was the "mystery monster" of the January 2026 Neowsletter.
You have to unlock the Underdocks before it can appear. Destructoid lists an "Underdocks" Epoch that unlocks an alternate Act 1 but does not give its requirement, and Mega Crit only says "once unlocked". IGN's "15 Biggest Changes" video (Mar 7, 2026) says "When you defeat all three overgrowth bosses, you'll unlock the underdocks"; the Unlocks and the Timeline page tracks the Epochs.
The boss is visible on the map from the first floor, so you can build toward it. The Acts and the Map page explains the rooms, and the Bosses page compares all of them.
How to read the numbers
Numbers are written base(higher): enemy HP rises at Ascension 8 and enemy damage at Ascension 9, so "56(58) HP" means 58 HP from Ascension 8. The tables come from OP.GG's monster guides, read from the game data of the public beta v0.111.0 (Aug 14, 2026); a row says so where a beta patch changed a number. See Ascension.
Normal enemies
The Underdocks' normal fights come from a fixed list. Mobalytics lists Corpse Slugs (duo or trio), Cultists (Calcified and Damp), Fossil Stalker, Gremlin Merc, Haunted Ship, Living Fog, Punch Construct, Seapunk, Sewer Clam, Sludge Spinner, Toadpoles and Two-Tailed Rats. Since v0.100.0 the Calcified Cultist comes with a Seapunk instead of a Toadpole.
| Enemy | HP | Moves |
|---|---|---|
| Corpse Slug | 25-27(27-29), Ravenous 4(5) | Whip Slap 3 x2; Glomp 8(9); Goop (2 Frail) |
| Calcified Cultist | 38-41(39-42) | Incantation (Ritual 2), then Dark Strike 9(11) every turn |
| Damp Cultist | 51-53(52-54) | Incantation (Ritual 5(6)), then Dark Strike 1(3) every turn |
| Fossil Stalker | 51-53(54-56), Suck 3 | Latch 12(14); Tackle 9(11) and 1 Frail; Lash 3(4) x2 |
| Gremlin Merc | 47-49(51-53), Surprise | Gimme 7(8) x2; Double Smash 6(7) x2 and 2 Weak; Hehe 8(9) and +2 Strength |
| Fat Gremlin | 13-17 | Flees |
| Sneaky Gremlin | 10-14 | Tackle 9(10) |
| Haunted Ship | 63(67) | Haunt (3 Weak, 5 Dazed) first; then Swipe 13(14) and Stomp 4(5) x3 in turn |
| Living Fog | 80(82) | Advanced Gas 8(9) and Smoggy; Bloat 5(6); Super Gas Blast 8(9); summons Gas Bombs |
| Gas Bomb | 7(8) | Explodes for 8(9) |
| Punch Construct | 55(60), Artifact 1 | READY (10 Block); Fast Punch 5(6) x2 and 1 Frail; Strong Punch 14(16) |
| Seapunk | 44-46(47-49) | Sea Kick 11(13); Spinning Kick 2 x4; Bubble Burp 7(8) Block and +1(2) Strength |
| Sewer Clam | 56(58), Plating 8(9) | Jet 10(11); Pressurize +4 Strength |
| Sludge Spinner | 37-39(41-42) | Oil Spray 8(9) and 1 Weak; Slam 11(12); Rage 6(7) and +3 Strength |
| Toadpole | 21-25(22-26) | Spike Spit 3(4) x3; Whirl 7(8); Spiken +2 Thorns |
| Two-Tailed Rat | 17-21(18-22) | Scratch 8(9); Disease Bite 6(7); Screech (1 Frail); Call for Backup (summons another rat) |
Source: OP.GG monster guides (game data, public beta v0.111.0), read Oct 26, 2026; encounter list from Mobalytics, read Oct 26, 2026.
The Gremlin Merc fight is a race for your Gold. Since v0.107.0 (on the main branch in Major Update #2), if the Merc stole nothing but the Fat Gremlin escaped, you get 50% of the normal Gold reward instead of none.
Three Underdocks fights were reworked on the main branch on Jun 19, 2026. Major Update #2 removed the Haunted Ship's Ramming Speed, reordered the Punch Construct's moves and switched its debuff from Weak to Frail; earlier, v0.103.0 stopped the Living Fog from adding more bombs over time.
Elites
The Underdocks' Elites are the Phantasmal Gardeners, the Skulking Colony and the Terror Eel, per Mobalytics. The Elites page covers every act.
| Elite | HP | Moves |
|---|---|---|
| Phantasmal Gardener (a group) | 26-31(27-32) each, Skittish 6(7) | Bite 5; Lash 7; Flail 1 x3; Enlarge +2(3) Strength |
| Skulking Colony | 75(80), Hardened Shell 20 | Zoom 14(16) on turns 1 and 2; Inertia 9(11) and +2(4) Strength; Piercing Stabs 7(8) x2 |
| Terror Eel | 140(150), Shriek 70(75) | Crash 16(18); Thrash 3(4) x3 and 6 Vigor; once stunned, Terrorize (99 Vulnerable on all players) |
Source: OP.GG monster guides (game data, public beta v0.111.0), read Oct 26, 2026.
The Skulking Colony caps how much damage it takes each turn. Its Hardened Shell is a per-turn damage cap of 20, and since Major Update #2 its health bar changes color when it can take no more damage that turn. Its HP went from 74(79) to 70(75) in v0.103.0 and back up to 75(80) in v0.106.0, when Mega Crit raised the Shell from 15 to 20, removed its Smash and stopped it gaining Block.
The Terror Eel is the Act 1 Elite players complain about most. Kotaku's Lewis Parker wrote, "Why the hell is some big-ass eel trying to hit me for 36 damage in Act 1, man?" v0.100.0 cut its Crash to 16(18) and its Thrash Vigor to 6. OP.GG's data gives it Shriek 70(75) and shows that once it is stunned it uses Terrorize, 99 Vulnerable on every player. It also has Phobia Mode visuals.
The Phantasmal Gardeners fight as a group. v0.100.0 cut each one's HP from 28-32 (29-33 at Ascension 8) to 26-31 (27-32).
Bosses
The Underdocks' boss is the Lagavulin Matriarch, Soul Fysh or Waterfall Giant.
| Boss | HP | Moves |
|---|---|---|
| Lagavulin Matriarch | 222(233) | Starts asleep; then Slash 19(21), Disembowel 9(10) x2, an attack of 12(14) with 12(14) Block, and Soul Siphon (-2 Strength and -2 Dexterity to all players, +2 Strength to itself) |
| Soul Fysh | 211(221) | Beckon (2 Beckon cards); De-Gas 16(17); Gaze 7(8) and 1 Beckon; Fade (2 Intangible); Scream 13(15) and 3 Vulnerable |
| Waterfall Giant | 240(250) | Pressurize (Steam Eruption 15(20)), then every move adds 3 more; Stomp 15(16) and 1 Weak; Ram 10(11); Siphon (heals 10(15)); Pressure Gun; Pressure Up 13(14); on death, About to Blow, then Explode |
Source: OP.GG monster guides (game data, public beta v0.111.0), read Oct 26, 2026; Soul Fysh's De-Gas is the main branch's 16(17), which the beta v0.111.0 raised to 16(18) per Mega Crit's notes.
Lagavulin Matriarch
The Lagavulin Matriarch is a slow fight against a boss that drains your stats. Game Rant's Marc Santos says it "has a tendency to turtle up with high amounts of Block while building up Strength and inflicting Strength and Dexterity debuffs". Each Soul Siphon costs you 2 Strength and 2 Dexterity and gives it 2 Strength, so long fights favor it.
Soul Fysh
Soul Fysh fills your draw pile with Beckon cards that hurt you if you hold them. Game Rant says Beckon cards in your hand at the end of your turn deal damage to you, and the boss also turns Intangible with Fade. Mega Crit raised its Scream from 11(12) to 13(15) in v0.105.0, on the main branch since Jun 19, 2026.
Waterfall Giant
The Waterfall Giant explodes when it dies. Its Steam Eruption grows with every move, and Game Rant warns that the blast at death deals damage based on its stacks, so you need enough HP or Block to survive it; in co-op only one player needs to. v0.101.0 cut its HP from 250(260) to 240(250), and Major Update #2 cut its heal from 15 to 10 below Ascension 9.
Events
The Underdocks has 9 events of its own in OP.GG's list, plus The Sunken Statue it shares with the Overgrowth and the shared pool. The Events page has them all.
| Event | Choices |
|---|---|
| Abyssal Baths | Immerse or Linger: gain 2 Max HP, take 3 damage, repeatedly; Abstain: heal 10 HP; or Exit Baths |
| Doors of Light and Dark | Dark Door: remove 1 card; or Light Door: Upgrade 2 random cards |
| Drowning Beacon | Bottle: the Glowwater Potion; or Climb: the Fresnel Lens, lose 13 Max HP |
| Endless Conveyor | Dishes at 40 Gold each (Max HP, healing, a Colorless card, a Transform, an Upgrade, a Potion and more); needs 120 Gold to appear |
| Punch Off | I Can Take Them: fight two Punch Constructs for greater rewards; or Nab: add Injury, a random Relic |
| Spiraling Whirlpool | Observe: Enchant a Basic Strike or Defend with Spiral; Drink: heal; or Reach In: a random Relic, add Writhe |
| Sunken Treasury | First Chest: 60 Gold; or Second Chest: 333 Gold and Greed (Unplayable, Eternal) |
| Trash Heap | Dive In: lose 8 HP, a "forgotten" Relic; or Grab Random Junk: 100 Gold and a "forgotten" card |
| Waterlogged Scriptorium | Bloody Ink: gain 6 Max HP; Tentacle Quill: 55 Gold to Enchant a card with Steady; or Prickly Sponge: 99 Gold to Enchant 2 cards with Steady |
Source: OP.GG event pages (public beta v0.111.0), read Oct 26, 2026.
The Trash Heap brings back items cut from the first game. OP.GG's page lists its relics (Darkstone Periapt, Dream Catcher, Hand Drill, Maw Bank, The Boot) and cards (Caltrops, Clash, Distraction, Dual Wield, Entrench, Hello World, Outmaneuver, Rebound, Rip and Tear, Stack), which the event calls "forgotten" items "from the past".
The Waterlogged Scriptorium got cheaper in April. v0.102.0 cut its prices from 65 and 155 Gold to 55 and 99.
Tips from the guides
The Underdocks rewards Block and quick kills. Kotaku advises taking area attacks and high-Block skills in Act 1 rather than committing to a build, noting that a starter deck often blocks only about 15 against 24-damage attacks.
Know the boss before the last Rest Site. Game Rant's advice is boss by boss: keep enough HP or Block for the Waterfall Giant's death blast, do not end turns holding Soul Fysh's Beckon cards, and expect the Lagavulin Matriarch to turtle behind Block while it drains your Strength and Dexterity.
Rest more than you think. PC Gamer's Austin Wood (Sep 18, 2026) says resting at every opportunity is the most reliable way through Act 1, and Mega Crit has spent its patches since March moving difficulty out of Act 1. The Pathing Guide covers routes.
Frequently asked questions
What is the Underdocks in Slay the Spire 2? The Underdocks is Slay the Spire 2's alternate Act 1, a flooded sewer of sea creatures and vagrants. Once it is unlocked, each run picks it or the Overgrowth by a coin flip.
How do you unlock the Underdocks in Slay the Spire 2? The Underdocks unlocks through an Epoch named "Underdocks" on Slay the Spire 2's Timeline, per Destructoid (Mar 7, 2026). IGN (Mar 7, 2026) says you unlock it by defeating all three Overgrowth bosses; Mega Crit has not stated the requirement itself.
What are the Underdocks bosses in Slay the Spire 2? The Underdocks' boss is the Lagavulin Matriarch (222 HP), Soul Fysh (211 HP) or the Waterfall Giant (240 HP). The map shows which one waits at the end of the act.
How do you beat the Waterfall Giant in Slay the Spire 2? Keep enough HP or Block to survive its death explosion, which deals damage based on its Steam Eruption stacks, Game Rant advises. In co-op only one player needs to survive the blast for the fight to count as won.
What does the Terror Eel do in Slay the Spire 2? The Terror Eel is an Underdocks Elite with 140 HP that hits for 16 with Crash and 3 x3 with Thrash; once it is stunned it applies 99 Vulnerable to every player. Kotaku's writer saw it threaten 36 damage in Act 1.
What is the Skulking Colony's Hardened Shell in Slay the Spire 2? Hardened Shell caps the damage the Skulking Colony takes each turn at 20 on the main branch v0.107.1. Its health bar changes color once you reach the cap for that turn.
Sources
- The Neowsletter - September 2025, Mega Crit, Sep 11, 2025
- The Neowsletter - January 2026, Mega Crit (Steam news), Jan 22, 2026
- Major Update #2 - v0.107.1, Mega Crit (Steam news), Jun 19, 2026
- Beta Patch Notes - v0.100.0, Mega Crit (Steam news), Mar 20, 2026
- Beta Patch Notes - v0.101.0, Mega Crit (Anthony Giovannetti, Steam news), Mar 27, 2026
- Beta Patch Notes - v0.102.0, Mega Crit (Steam news), Apr 3, 2026
- Beta Patch Notes - v0.103.0, Mega Crit (Steam news), Apr 10, 2026
- Beta Patch Notes - v0.105.0, Mega Crit (Steam news), May 8, 2026
- Beta Patch Notes - v0.111.0, Mega Crit (Steam news), Aug 14, 2026
- Slay the Spire 2 Monsters, OP.GG (game data, public beta v0.111.0), read Oct 26, 2026
- Slay the Spire 2 Events, OP.GG (public beta v0.111.0), read Oct 26, 2026
- Trash Heap, Slay the Spire 2 Event, OP.GG (public beta v0.111.0), read Oct 26, 2026
- Slay the Spire 2 Monsters, Mobalytics, read Oct 26, 2026
- Slay the Spire 2 Elites, Mobalytics, read Oct 26, 2026
- How to unlock all Epochs in Slay the Spire 2, Destructoid (Arka Sarkar), Mar 7, 2026
- All Acts, Biomes, and Bosses in Slay the Spire 2, Game Rant (Marc Santos), Mar 12, 2026
- Slay The Spire 2: Tips And Tricks For Getting Started, Kotaku (Lewis Parker), Mar 18, 2026
- After 894 hours in Slay the Spire 2, these are our 12 strongest opinions, PC Gamer (Evan Lahti, Harvey Randall, Austin Wood), Sep 18, 2026
- Slay the Spire 2 - 15 Biggest Changes From Slay the Spire 1, IGN, Mar 7, 2026 (video)
- The game just got 200% harder | Spire 2 Patch Rundown V0.106.0, JapaneseExport, May 22, 2026 (video)
- How to Beat EVERY Elite in Slay the Spire 2 (Full Guide), Nerdy Hickey, Apr 15, 2026 (video)
- The Secret to Beating EVERY Boss on Ascension 10 | Slay the Spire 2 Guide, vmService, Jun 16, 2026 (video)
- The Optimal Choice for EVERY Event in Slay the Spire 2, vmService, Aug 25, 2026 (video)
Moments
Slay the Spire 2 - 15 Biggest Changes From Slay the Spire 1
IGN
The game just got 200% harder | Spire 2 Patch Rundown V0.106.0
JapaneseExport
How to Beat EVERY Elite in Slay the Spire 2 (Full Guide)
Nerdy Hickey
The Secret to Beating EVERY Boss on Ascension 10 | Slay the Spire 2 Guide
vmService
- The Lagavulin Matriarch is a slow fight against a boss that drains your stats. Game Rant's Marc Santos says it "has a…
- Soul Fysh fills your draw pile with Beckon cards that hurt you if you hold them. Game Rant says Beckon cards in your…
- The Waterfall Giant explodes when it dies. Its Steam Eruption grows with every move, and Game Rant warns that the…
The Optimal Choice for EVERY Event in Slay the Spire 2
vmService
Related
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ArchitectThe Architect is the figure at the top of the Spire who ends every Slay the Spire 2 run after the Act 3 boss, killing you before you can play a card; in Early Access there is no Act 4, no keys and no true ending, which Mega Crit promises for the 1.0 release.
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ElitesSlay the Spire 2 has 12 Elite fights in Early Access, three in each of its four areas (Overgrowth, Underdocks, Hive and Glory), and every Elite drops a relic along with a card reward. Ascension 1, Swarming Elites, makes them appear more often.
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EnemiesSlay the Spire 2's normal enemies differ in each of its four areas (the Overgrowth and Underdocks in Act 1, the Hive in Act 2 and Glory in Act 3), with HP that rises at Ascension 8 and damage that rises at Ascension 9. The in-game Bestiary, added in v0.105.0, shows the moves of every monster you have met.
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GloryGlory is Act 3 of Slay the Spire 2, the upper Spire, whose Elites are the Knight Trio, the Mecha Knight and the Soul Nexus and whose boss is Aeonglass, the Queen or the Test Subject; at Ascension 10 you fight two of them.
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CardsSlay the Spire 2's game data holds 577 cards on the main branch (v0.107.1): about 88 for each of the five characters, 64 Colorless, 18 curses, 16 statuses, 3 Quest cards, and Event, Ancient and Token cards. Cards are Attacks, Skills, Powers, Statuses, Curses or Quests; rarities run Basic, Common, Uncommon, Rare and Ancient; card rewards offer 3 cards and you take 1.
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Colorless CardsSlay the Spire 2 has 64 Colorless cards on its main branch (v0.107.1), 39 Uncommon and 25 Rare, that any character can use; 11 of them appear only in co-op. You get them from the Merchant (2 a visit), Neow's Lead Paperweight, events, relics such as Dingy Rug and Toolbox, and cards that create them, such as Jack of All Trades and the Regent's.
See also
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OvergrowthThe Overgrowth is one of the two possible first acts of Slay the Spire 2, a jungle ruin chosen by a coin flip against the Underdocks, with the Elites Bygone Effigy, Byrdonis and Phrog Parasite and the bosses Ceremonial Beast, The Kin and Vantom.
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HiveThe Hive is Act 2 of every Slay the Spire 2 run, an insect nest whose Elites are the Decimillipede, Entomancer and Infested Prism and whose boss is the Kaiser Crab, the Knowledge Demon or The Insatiable; an Ancient greets you at its start.
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Unlocks and the TimelineSlay the Spire 2 unlocks its characters in a chain by playing one run (win or lose) with each: the Ironclad unlocks the Silent, then the Regent, the Necrobinder and the Defect. Everything else (cards, relics, potions, Ancients, the Underdocks, Ascension, Daily and Custom runs) comes from 57 Epochs on the Timeline, earned by goals such as beating an act or by spending score; Daily and Custom runs earn none.
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Acts and the MapA Slay the Spire 2 run climbs three acts, the Overgrowth or the Underdocks (a coin flip), then the Hive, then Glory, each opening with an Ancient and ending in a boss, before the Architect ends the climb. Each act is a branching map of combat, Elite, ? (Unknown), Merchant, Treasure and Rest Site rooms; Game Rant puts a run at about 45 to 50 encounters and up to about 40 minutes.
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BossesSlay the Spire 2 has 12 bosses in Early Access, three per act: Ceremonial Beast, The Kin and Vantom (Overgrowth), Lagavulin Matriarch, Soul Fysh and Waterfall Giant (Underdocks), Kaiser Crab, Knowledge Demon and The Insatiable (Hive), and Aeonglass, Queen and Test Subject (Glory).