Grand Underground

This section is incomplete. Please feel free to edit this section to add missing information and complete it. Reason: Individual pages for Hideaways with details on encounters, list of items able to be exchanged with merchants, list of pedestals

Grand Underground 地下大洞窟 Grand Underground Cave "Wild Missingno. appeared!"
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Location:	Beneath Sinnoh
Region:	Sinnoh
Generations:	VIII
Location of Grand Underground in Sinnoh.
Pokémon world locations

The Grand Underground (Japanese: 地下大洞窟 Grand Underground Cave) is an area in Pokémon Brilliant Diamond and Shining Pearl found beneath the entire Sinnoh region. Players can travel to the Grand Underground using an Explorer Kit, given to the player by Underground Man in Eterna City.

It takes the place of the Underground from Pokémon Diamond, Pearl, and Platinum.

Changes from Diamond and Pearl

Lucas and Dawn in the Grand Underground

Digging

• The map now conforms to the shape of the Sinnoh landmass instead of a large square layout. Notably, it excludes Iron Island, Fullmoon Island, and Route 223 onwards, however the Explorer Kit is usable on Fullmoon island but not the other locations.
• The map is still split into six disjoint areas like the original Underground, but the sizes and locations of the six areas do not match those of the original Underground.
• Areas now include Pokémon Hideaways, and each area now corresponds to a different aesthetic environment.
• The digging minigame returns following closely to its original incarnation with the exception of digging up Pokémon statues, which come from Stone Boxes.
  • If the player runs out of digging spots, more will appear once the player enters and exits a Hideaway.
  • After the Sinnoh Pokedex is completed, Mysterious Shard S and Mysterious Shard L will start appearing in the underground.
• Secret Bases return and are created using a Digger Drill as before.
  • Bases can only be decorated with statues and pedestals to place them on.
  • The flag stealing mechanic has been removed.
• Goods and Traps, with the sole exception of the Digger Drill, have been removed.
• Spheres no longer have a numerical size and are instead categorized as Small or Large. They can no longer be buried either.
• Instead of goods or traps, merchants (who appear as Hikers) in the Grand Underground can exchange treasures and for spheres. Spheres can now be exchanged for pedestals, items, and TMs.
  • Some Hikers found in the Grand Underground allow the player to rest, acting as a Pokémon Center.
• The radar is now triggered by pressing [R] and searches the area around the player's location.
• The Grand Underground supports online communications, compared to the original games which only supported local communications.
• Diglett and Dugtrio will occasionally pop out and leave pink sparkles that give 1 and 3 points respectively. Accumulating 40 of these points causes "something good to happen" which increases the shiny odds for Pokémon in Hideaways to 1/2048 for a period of 4 minutes. Additionally, all Stone Boxes found while digging during the 4 minute bonus period will be Gorgeous Stone Boxes. A whistle is heard when this period begins and once more when it ends. The bonus and progress gauge is shared between all players connected to the same instance of the Grand Underground. If all connected players leave the Grand Underground, this gauge resets to zero.
• Steps taken in the Grand Underground count towards Egg distance as well as the step counter app.

Zones

The Grand Underground is organized into six zones, with each zone containing Pokémon Hideaways.

Zone	Map
Central
East and West
North-western
North-eastern
South-western
South-eastern

Pokémon Hideaways

Pokémon Hideaway

Pokémon Hideaways (Japanese: ポケモンの隠れ家 Pokémon Hideaway) are new places where wild Pokémon can be encountered. Unlike the main overworld, these areas feature symbol encounters. Each of the six areas contain at least one large Hideaway (known as Caverns), and multiple, smaller Hideaways (known as Caves) scattered throughout the map. Various hideaways - particularly larger areas - include items for Trainers to discover, such as Deep Sea Scale. Some Pokémon available in the game can only be found in Hideaways. At least three areas include surfable water. These hideaways are the Swampy Cave, Lakeside Cave and the Glacial Cavern.

Caves

Icon	Name
	Dazzling Cave
	Fountainspring Cave
	Grassland Cave
	Icy Cave
	Riverbank Cave
	Rocky Cave
	Sandsear Cave
	Spacious Cave
	Swampy Cave
	Volcanic Cave
	Whiteout Cave

Caverns

Icon	Name
	Big Bluff Cavern
	Bogsunk Cavern
	Glacial Cavern
	Stargleam Cavern
	Still-Water Cavern
	Sunlit Cavern
	Typhlo Cavern

The variety of Pokémon encountered increases at five milestones - obtaining TM97 Defog, obtaining TM96 Strength, earning the Icicle Badge, obtaining TM99 Waterfall, and unlocking the National Pokédex. Earning each badge earned will also increase the strength of the Pokémon encountered. The player does not need to be able to use the TM outside battle in order for more variable Pokémon to appear. All Pokémon in the Hideaways will have at least one Egg Move if applicable, and The Grand Underground also unlocks some Egg Moves that would otherwise be unobtainable, e.g. Aura Sphere for Squirtle.

Progression	Level Ranges
1 Badge	16-20
2 Badges	25-29
3 Badges	29-33
4 Badges	33-37
5 Badges	36-40
6 Badges	39-43
7 Badges	42-46
8 Badges	50-55
Elite Four defeated	58-63

Secret Base

Secret Base with Standard and Color statues

Similar to Pokémon Diamond, Pearl, and Platinum, the player is able to create a Secret Base within the Grand Underground using a Digger Drill. However, unlike the previous games, the Secret Base can only be decorated with statues and pedestals to place them on.

Statues can be obtained from Stone Boxes. Stone Boxes can be found by digging, similar to spheres and fossils. There are two kinds of Stone Boxes, the common Pretty Stone Boxes and the rare Gorgeous Stone Boxes. There is a box for each type.

Standard statues are obtained from Pretty Stone Boxes, while Color statues are acquired from Gorgeous Stone Boxes. Color statues appear to be made of jade and seemingly depict Shiny Pokémon, due to the statues' names having the shiny symbol next to it.

Stone Box	Normal	Fighting	Flying	Poison	Ground	Rock	Bug	Ghost	Steel
Pretty
Gorgeous
Stone Box	Fire	Water	Grass	Electric	Psychic	Ice	Dragon	Dark	Fairy
Pretty
Gorgeous

Each statue placed in the Secret Base increases the chance of encountering a Pokémon of the corresponding type in Hideaways. Only the type with the greatest number of statues of the corresponding type will have a boosted effect, which is indicated by the color of the orb placed next to the entrance of the player's base. This "Statue Effect" is increased for every statue of that type that is placed in the player's Secret Base. If the Pokémon has two types, the primary type of the Pokémon has a greater effect than its secondary type in determining which type has a boosted effect. Hence, if only one statue of a dual-typed Pokémon is placed, the boosted type will correspond to the Pokémon's primary type. Furthermore, larger statues and Color statues provide a greater effect. A maximum of 18 statues can be placed at one time.

A player's chance of finding a Gorgeous Stone Box can be temporarily increased for four minutes by collecting 40 Diglett that can be found scattered throughout the Grand Underground. Each Diglett counts as one towards the tally, while encountering a Dugtrio counts as three. This count is reset when the player leaves the Grand Underground.

The size of the Secret Base can be expanded by exchanging spheres with one of the merchants in the Grand Underground. Like in the original, a player can only have a single base at a time.

Merchants

Spheres can be used to exchange for pedestals and various items, such as TMs. There are three types of merchants in the Grand Underground:

• Small sphere merchants allow the player to purchase additional Digger Drills, small or medium pedestals, and TMs which change daily.
• Large sphere merchants who offer large or extra large pedestals, and a different set of TMs.
• An item exchange merchant, who will give spheres in exchange for items that can be dug out. Additionally, he can also be paid to expand the player's Secret Base.

Number of spheres required	Expansion
Red Sphere S ×60 Blue Sphere S ×60 Green Sphere S ×60 Prism Sphere S ×30 Pale Sphere S ×30	Increases size of Secret Base to 14×8 tiles
Red Sphere L ×40 Blue Sphere L ×40 Green Sphere L ×40 Prism Sphere L ×20 Pale Sphere ×20	Increases size of Secret Base to 14×10 tiles

Trivia

• Despite the change in the layout, the Grand Underground maintains rotational symmetry, similar to the Underground.

In other languages

Language Title Chinese Cantonese 地下大洞窟 Deihhah Daaihduhngfāt Mandarin 地下大洞窟 Dìxià Dàdòngkū French Grands Souterrains German Untergrundhöhlen Italian Grandi Sotterranei Korean 지하대동굴 Jiha Daedonggul Russian Великое подземелье Velikoye podzemel'ye Spanish Grutas del Subsuelo

Pokémon Hideaway

Language Title Chinese Cantonese 寶可夢秘巢 Pokémon Beichàauh Mandarin 寶可夢秘巢 / 宝可梦秘巢 Pokémon Mìcháo French Cachette de Pokémon German Pokémon-Unterschlupf Italian Rifugio di Pokémon Korean 포켓몬 은신처 Pokémon Eunsincheo Russian Укрытие Покемонов Ukrytiye Pokémonov Spanish Guarida Pokémon

Sinnoh
Settlements Twinleaf Town • Sandgem Town • Jubilife City • Oreburgh City • Floaroma Town • Eterna City • Hearthome City Solaceon Town • Veilstone City • Pastoria City • Celestic Town • Canalave City • Snowpoint City • Sunyshore City Pokémon League • Fight Area • Survival Area • Resort Area Routes 201 • 202 • 203 • 204 • 205 • 206 • 207 • 208 • 209 • 210 • 211 • 212 • 213 • 214 • 215 216 • 217 • 218 • 219 • 220 • 221 • 222 • 223 • 224 • 225 • 226 • 227 • 228 • 229 • 230 Landmarks Lake Verity (Lakefront) • Oreburgh Gate • Oreburgh Mine • Oreburgh Mining Museum • Global Terminal/Global Wonder Station Ravaged Path • Floaroma Meadow • Valley Windworks • Eterna Forest • Old Chateau • Underground/Grand Underground Wayward Cave • Mount Coronet • Amity Square • Lost Tower • Hallowed Tower • Solaceon Ruins • Maniac Tunnel • Lake Valor (Lakefront) Great Marsh • Pokémon Mansion • Trophy Garden • Fuego Ironworks • Iron Island • Lake Acuity (Lakefront) • Spear Pillar • Victory Road Pal Park/Ramanas Park • Contest Hall • Battle Zone • Battle Park • Battle Tower/Battle Frontier • Stark Mountain • Snowpoint Temple Spring Path • Sendoff Spring • Turnback Cave • Fullmoon Island • Newmoon Island • Seabreak Path • Flower Paradise • Hall of Origin Access to Distortion World See also Hisui

This article is part of Project Locations, a Bulbapedia project that aims to write comprehensive articles on every location in the Pokémon world.