Pokémon Diamond and Pearl/The Underground

The underground contains similar aspects of Spectrobes in it. This is because you can scan the ground with your Stylus, and you can locate sparkles on the ground. If they are in a wall, you can dig them up and exavate colored orbs. Orbs come in several different colors; red, blue, green, and yellow. There are also treasures such as Prism Spheres or rare Diamond and Pearl Items, such as Moon Stones, Thunderstones, and Heart Scales.

If the sparkle is just on the ground, do not step on it as it may be a trap. Instead, go to the square in front of it and press . You will disengage the trap and you can set it wherever you wish. The other thing a sparkle on the ground could be is a buried Sphere.

You also have a radar on the top screen that tells you where hidden objects are. They appear all the time as little sparkles on the radar.

You can also make Secret Bases in the Underground, which are very similar to those from Pokémon Ruby and Pokémon Sapphire. Unlike Ruby and Sapphire, however, you must obtain a Digger Drill from the Underground Man or trade for one in the Underground. Once you do this, go to "Traps" and use your Drill on a wall space. Once you do this, the Drill will break, and if you want to move your Base you'll have to acquire a new one.

You can also decorate your Secret Base. You can put up to 15 items at a time in your Base, and if you want different ones you'll have to switch out a few items. You can get decorations from three different places: the Underground Man, the Veilstone Department Store, or the Battle Tower. The Underground Man gives you a few basic items once you create a first Secret Base with the Digger Drill he gives you. You can buy unlimited copies of decorations from the Veilstone Department Store, and You can get trophies for beating certain amounts of trainers in a row at the Battle Tower.

There are several items that are obtainable in the underground, but they can be grouped into three categories: Fossils, Treasures, and Spheres.

Spheres

Spheres are the most common items in the underground. They can be obtained by excavating them when you dig into a wall. Almost every single wall contains at least one Sphere.

You have a limit to how many Spheres you can carry (about 35), so obviously you will have to get rid of some. However, you can do something more worthful than just throwing them away. You can bury them in the ground, and they will grow in size every day. if you wait several days, even the tiniest sphere can be turned into a size 60 or larger!

Sphere List

Name/Color	Rarity
Blue Sphere	Very Common
Red Sphere	Common
Green Sphere	Common
Pale Sphere	Uncommon
Prism Sphere	Rare

Fossils

Fossils are very rare items in the Underground that can be turned into level 20 Pokémon at the Coal Mining Museum in Oreburgh City. Leave the laboratory, then re-enter, to allow the scientist enough time to resurrect the Pokémon.

Fossil List

Name	Pokémon Revived Into
Skull Fossil	Cranidos (Diamond Only)
Armor Fossil	Shieldon (Pearl Only)
Dome Fossil	Kabuto (National Pokedex needed)
Helix Fossil	Omanyte (National Pokedex needed)
Claw Fossil	Anorith (National Pokedex needed)
Root Fossil	Lileep (National Pokedex needed)
Old Amber	Aerodactyl (National Pokedex needed)

Treasures

Treasures are rare items in the Underground that can be put into your Bag in the overworld. They can be items to sell, rare Type-boosting items, or rare weather-prolongers.

Treasure List

Name	Effect
Moon Stone	Evolves certain Pokémon
Leaf Stone	Evolves certain Grass-Type Pokémon
Fire Stone	Evolves certain Fire-Type Pokémon
Water Stone	Evolves certain Water-Type Pokémon
Sun Stone	Evolves certain Pokémon
Thunderstone	Evolves certain Electric-Type Pokémon
Hard Stone	boosts Rock-Type moves' power
Zap Plate	boosts Electric-Type moves' power
Toxic Plate	boosts Poison-Type moves' power
Meadow Plate	boosts Grass-Type moves' power
Iron Plate	boosts Steel-Type moves' power
Stone Plate	boosts Rock-Type moves' power
Earth Plate	boosts Ground-Type moves' power
Mind Plate	boosts Psychic-Type moves' power
Icicle Plate	boosts Ice-Type moves' power
Spooky Plate	boosts Ghost-Type moves' power
Fist Plate	boosts Fighting-Type moves' power
Draco Plate	boosts Dragon-Type moves' power
Fire Plate	boosts Fire-Type moves' power
Insect Plate	boosts Bug-Type moves' power
Splash Plate	boosts Water-Type moves' power
Dread Plate	boosts Dark-Type moves' power
Sky Plate	boosts Flying-Type moves' power
Light Clay	Extends the turns the moves Reflect and Light Screen last
Iron Ball	Reduces holder's Speed, and makes Flying Types and Pokémon with the ability Levitate susceptible to Ground Type moves
Ice Rock	lengthens the amount of turns of the move Hail
Heat Rock	lengthens the amount of turns of the move Sunny Day
Smooth Rock	lengthens the amount of turns of the move Sandstorm
Damp Rock	lengthens the amount of turns of the move Rain Dance
Heart Scale	paid to the Move Relearner so your Pokémon can relearn a move
Revive	revives a fainted Pokémon and restores its HP by 1/2
Max Revive	Revives a fainted Pokémon to full HP
Everstone	keeps the holder from evolving
Star Piece	can be sold for a high price at shops(4900)
Rare Bone	can be sold for a high price at shops(5k)
Odd keystone	can be placed in the hollowed tower to catch Spiritomb.

Flags

The Flags are obtainable from other players' Secret Bases, at their PCs. Obtaining a flag greatly boosts your Underground score, plus obtaining enough flags gains you upgrades for your Secret Base.

Colour	Flags Needed	Items Placeable	Removable boulders
Regular Flag	0	10	0
Bronze Flag	1	13	2
Silver Flag	3	14	4
Gold Flag	20	15	6
Platinum Flag	50	15	All

The Platinum flag also upgrades your Trainer Card by one star.