Ancient Caustic Sewers

Ancient Caustic Sewers, also known as ACS, is the continuation dungeon of Caustic Sewers. The green water in this dungeon can Poison a Water, Flying, or levitating Pokémon, so bringing a Pokémon with Refresh (or part Steel) will help you throughout this dungeon.

Attributes
The dungeon is light green in color and has light green water. Rooms are usually very compact and small.

End Box

 * Purity Relic
 * Poison Dust
 * Full Restore
 * Max Revive
 * Old Gateau
 * Big Nugget
 * TM Sludge Bomb
 * TM Poison Jab
 * TM Venoshock

Secret Room
The room contains 2 Deluxe Boxes, by which could contain these items:
 * Poison Dust
 * Golden Apple
 * Revive
 * Revival Herb
 * Big Nugget
 * Relic Vase
 * TM Sludge Bomb
 * TM Sludge Wave
 * TM Venoshock

Pokémon
''Pokémon in bold are recruitable. Please visit the Recruitable Pokémon page for more information.''

Kecleon Shop Items
There is a Kecleon Shop on Floor 12.

Dungeon Objective
Mainly, the dungeon objective is to clear it and also recruiting Solosis or Ferroseed. Additionally Purity Relic is exclusive to the end box of this dungeon.

Tips

 * Caustic Sewers and by extension Ancient Caustic Sewers are great for farming Ekop.

Trivia

 * This is the highest level dungeon in Tanren Undercity.