Ancient Caustic Sewers (Sewers, ACS) is the continuation of Caustic Sewers. It is void of weather like Caustic Sewers.
Attributes
| Traps | |
|---|---|
| Icon | Name |
|
Explosion Trap |
|
Grimy Trap |
|
Gust Trap |
|
Mud Trap |
|
Pitfall Trap |
|
PP-Zero Trap |
|
Seal Trap |
|
Selfdestruct Trap |
|
Shocker Trap |
|
Slumber Trap |
|
Spikes Trap |
|
Spin Trap |
|
Spring Trap |
|
Sticky Trap |
|
Summon Trap |
|
Toxic Spikes Trap |
|
Trip Trap |
|
Warp Trap |
|
Wonder Tile |
The dungeon is light green in color, there's rather heavy darkness and rooms are usually very compact and small. Water continues to poison Pokémon who are not immune or protected from it.
On Floor 15 is a sealed chamber.
Box items:
Pink Silk- Golden Apple
- Max Revive
- Big Nugget
Boss
The player finds Team Skull, a Reuniclus and three Solosis at the end of the dungeon. Reuniclus and the Solosis are accused of causing the leakage in the sewers because of the substance that covers their bodies. The Reuniclus was unaware of the leakage issue and has no connection, and the player interferes with Team Skull to prevent any harm done to the Reuniclus in spite of that.
Unlike in Caustic Sewers, Team Skull has the following moves in Ancient Caustic Sewers:
- Koffing: Dark Pulse, Facade, Sludge Bomb, Thunderbolt
- Skuntank: Flamethrower, Poison Jab, Shadow Claw, Throat Chop
- Zubat: Aerial Ace, Leech Life, Shadow Ball, Venoshock
Boss drop:
- 30 Ekop (Skuntank)
- Skull Brooch (Zubat)
- 1 Mushroom (Zubat, Koffing)
Dialogue:
- Skuntank: Chaw-haw-haw! That settles it! It's your group of crummy Pokémon causing all of that nasty waste to leak into the sewers!
- Skuntank: Just look at all of that filthy liquid leaking from your bodies... Yuck! One Night Slash, and this problem's dealt with!
- Reuniclus: W-We weren't aware! We f-found this place for us to settle and for the Solosis here to g-grow and get stronger... Please!
- Skuntank: Stop your yapping! We couldn't care less. The only thing that matters here is that Team Skull has to get rid of you!
- Skuntank: And then, we can claim our grand reward! Perhaps finally settle into our rightfully earned paradise resort in Archford... Chaw-haw-haw!
- Skuntank: ...?!
- Skuntank: Oh, just great... The little brats are back.
- (You try to convince Team Skull that the Reuniclus did not have bad intentions)
- Skuntank: Enough! Stop talking! Team Skull does not care about some brat's dull fairy tales.
- Skuntank: Chaw-haw-haw! This reward's ours, and ours alone! If you're going to stand in our way, we'll just have to beat you up again!
- Skuntank: And with these new TMs, that'll be childs play. You don't stand a chance!
- Koffing: Woah-ho-ho! Aye aye, chief!
- Zubat: Heh-heh! Let's get 'em!
- Skuntank: Come on, boys!
- Team Skull: YEAH!
- Skuntank: Chaw... haw-haw. Not again...
- Koffing: Woah... ho-ho. They're strong...
- Zubat: Wheh-heh-heh... Just how...?
- Skuntank: We've failed... But we can't come back empty handed! We'll just make something up!
- Koffing: Woah-ho-ho! Good idea, Chief!
- Skuntank: Let's get out of here! Let these little brats fight it out together, while we'll take the credit! Chaw-haw-haw!
- Zubat: Heh-heh! Perfect!
- Team Skull: YEAH!
- (Team Skull hastily makes their way out...)
- Reuniclus: T-Thank you so much! I was so scared...
- Reuniclus: Those poor little Solosis... H-How could those guys be so mean to them?
- Reuniclus: The poison leaking from here... It's n-not our fault! We didn't do anything!
- Reuniclus: There's a r-reward right after this room... Some goodies we managed to collect in here. It's not much, but it's the best I could do to thank you...
- Reuniclus: Little S-Solosis... Let's go! We're saved...
- Reuniclus: T-thank you...
Forgotten Shrine
In the end room there are two Deluxe Boxes.
Box items:
- Purity Relic
- Poison Dust
- Old Gateau
- Full Restore
- Max Revive
- Big Nugget
- TM Poison Jab
- TM Sludge Bomb
- TM Venoshock
Secret Room
The Secret Room contains two Deluxe Boxes, and it is found on all floors besides the last.
Box items:
- Poison Dust
- Golden Apple
- Revival Herb
- Revive
- Big Nugget
- Relic Vase
- TM Sludge Bomb
- TM Sludge Wave
- TM Toxic
- TM Venoshock
Pokémon
Pokémon in bold are recruitable. Please visit the Recruitable Pokémon page for more information.
| Portrait | # | Pokémon | Floor | Recruit rate |
|---|---|---|---|---|
 | 024 | Arbok | B1-15F | Unrecruitable |
 | 073 | Tentacruel | B1-15F | Unrecruitable |
 | 031 | Nidoqueen | B1-15F | Unrecruitable |
 | 034 | Nidoking | B1-15F | Unrecruitable |
 | 088 | Alolan Grimer | B1-15F | 4.2% |
| 089 | Alolan Muk | B1-15F | Unrecruitable |
 | 317 | Swalot | B1-15F | Unrecruitable |
 | 336 | Seviper | B1-15F | Unrecruitable |
 | 435 | Skuntank | B1-15F | Unrecruitable |
 | 454 | Toxicroak | B1-15F | Unrecruitable |
 | 452 | Drapion | B1-15F | Unrecruitable |
 | 569 | Garbodor | B1-15F | Unrecruitable |
 | 577 | Solosis | B1-15F | 5% |
 | 578 | Duosion | B1-15F | Unrecruitable |
 | 579 | Reuniclus | B1-15F | Unrecruitable |
 | 597 | Ferroseed | B1-15F | 5% |
 | 598 | Ferrothorn | B1-15F | Unrecruitable |
| 758 | Salazzle | B1-15F | Unrecruitable |
Items
| IS | Item | Location | Tile | Hidden |
|---|---|---|---|---|
 | 1-5 Ekop | B1-15F | Floor | No |
 | Black Sludge | B1-15F | Floor | No |
 | Sticky Barb | B1-15F | Floor | No |
 | Pecha Scarf | B1-15F | Floor | No |
 | Poison Barb | B1-15F | Floor | No |
 | Poison Diamond | B1-15F | Floor | No |
 | Grimy Berry | B1-15F | Floor | No |
 | Grimy Food | B1-15F | Floor | No |
 | Ether | B1-15F | Floor | No |
 | Max Ether | B1-15F | Floor | No |
 | Antidote | B1-15F | Floor | No |
 | Oran Berry | B1-15F | Floor | No |
| Oren Berry | B1-15F | Floor | No |
 | Kebia Berry | B1-15F | Floor | No |
 | Plain Seed | B1-15F | Floor | No |
 | Reviver Seed | B1-15F | Floor | No |
 | Gummis | B10-15F | Floor | No |
 | Toxic Spike | B1-15F | Floor | No |
 | Rare Bone | B1-15F | Floor | Yes |
 | Relic Copper | B1-15F | Floor | No |
 | Relic Silver | B1-15F | Floor | No |
 | Relic Gold | B1-15F | Floor | No |
 | All-Dodge Orb | B1-15F | Floor | No |
 | All-Hit Orb | B1-15F | Floor | No |
 | All Power-Up Orb | B1-15F | Floor | No |
 | All Protect Orb | B1-15F | Floor | No |
 | Cleanse Orb | B1-15F | Floor | No |
 | Health Orb | B1-15F | Floor | No |
 | Luminous Orb | B1-15F | Floor | No |
 | Nullify Orb | B1-15F | Floor | No |
 | Recycle Orb | B1-15F | Floor | No |
 | See-Trap Orb | B1-15F | Floor | No |
 | Trawl Orb | B1-15F | Floor | No |
 | Big Mushroom | B1-15F | Floor | Yes |
 | Heart Scale | B1-15F | Wall | Yes |
Kecleon Shop
There is a Kecleon Shop on Floor 12.
| IS | Item | Price |
|---|---|---|
| Black Sludge |  500 Poké |
 | Toxic Orb | 500 Poké |
 | Big Yellow Apple | 250 Poké |
| Max Ether | 250 Poké |
| Antidote | 250 Poké |
 | Revival Herb | 3500 Poké |
| Oran Berry | 100 Poké |
 | Sitrus Berry | 150 Poké |
 | Lum Berry | 150 Poké |
| Reviver Seed | 2500 Poké |
 | TM Poison Jab | 5000 Poké |
| TM Sludge Bomb | 5000 Poké |
| TM Toxic | 5000 Poké |
| Recycle Orb | 350 Poké |
 | Scanner Orb | 350 Poké |
| Trawl Orb | 350 Poké |
Mystery Eggs
Ancient Caustic Sewers has Mystery Eggs that can appear on all floors.
| Portrait | # | Pokémon | Location | Tile | Hidden |
|---|---|---|---|---|---|
|
|
577 | Solosis | B1-15F | Floor | No |
|
|
597 | Ferroseed | B1-15F | Floor | No |
Dungeon Objective
The Purity Relic and Skull Brooch are both items exclusive to this dungeon. A Pink Silk can be obtained here alongside Caustic Sewers. Players often come to this dungeon to earn Ekop for the various shops in the Tanren Undercity.
Tips
- A way to heal or prevent statuses (mainly poison) is recommended.
- As with Caustic Sewers, beware of Garbodor and Skuntank's Aftermath ability.
Trivia
- This is the highest level dungeon in Tanren Undercity.