"I have here the Vortex Stone. Bearing it, you will gain passage through the sea's tornadoes... It will lead you to a place called the Silver Trench. There, you will find the guardian of the sea. Now go. The guardian of the sea awaits you."

–Articuno, Zapdos, and Moltres's description of the Silver Trench

"With your life at stake... Bring it on!"

–Lugia before its boss battle at the end of the dungeon

Silver Trench is a dungeon in Pokémon Mystery Dungeon: Red Rescue Team and Blue Rescue Team. You can only access this dungeon after recruiting all the legendary birds, Pitfall Valley and Stormy Sea has been cleared, and after talking to Alakazam and visit the Legendary Island. The Move/HM Dive and a Water Pokemon is required to enter the dungeon.

Monster Houses are set to appear at the 15th, 35th, 55th, and 75th floors, all with rooms akin to rooms under the effects of the One-Room Orb. Bringing powerful Pokémon with moves that effect the entire room (Articuno with Powder Snow is an excellent choice)

On the last floor, Lugia awaits. Even if Lugia is known for its devastating power, it is only level 30 and knows the moves Whirlwind, Gust, and Safeguard. On the bright side, it also has a 99.9% recruitment rate. After Lugia has been recruited, Meteor Cave, where Deoxys resides, will be unlocked.