Ancient Caustic Sewers

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.

Bosses
Portrait	#	Pokémon	Type	Drops	Moves
	041	Zubat		Skull Brooch 1 Mushroom	Aerial Ace Range: 4 Effect: Inflicts damage. Never misses. Leech Life Range: 5 Effect: Inflicts damage. Restores HP of the user by 50% the damage inflicted. Shadow Ball Range: 10 Effect: Inflicts damage. May lower the target's Special Defense stat by 1 stage. Cannot affect targets with Bulletproof. Venoshock Range: 3 Effect: Inflicts damage. Power is doubled if the target is poisoned.
	109	Koffing		1 Mushroom	Dark Pulse Range: 2 Effect: Inflicts damage. May make the target cringe. Facade Range: 2 Effect: Inflicts damage. Power is doubled if the user is inflicted with a non-volatile status condition. Sludge Bomb Range: 5 Effect: Inflicts damage. May poison the target. Cannot affect targets with Bulletproof. Thunderbolt Range: 2 Effect: Inflicts damage. May paralyze the target.
	435	Skuntank		30 Ekop	Flamethrower Range: 10 Effect: Inflicts damage. May burn the target. Poison Jab Range: 2 Effect: Inflicts damage. May poison the target. Shadow Claw Range: 2 Effect: Inflicts damage. Has an increased critical hit rate. Throat Chop Range: 2 Effect: Inflicts damage and silences the target.

Dialogue:

Before fighting

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!

After defeating

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.

#	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

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.