A Sphere (Japanese: タマ Sphere) is the basic unit of currency in the Underground of Sinnoh. They come in five colors: Red, Blue, Green, Prism, and Pale. These correspond to different versions of the Pokémon games, with the first three matching the original colors of Red, Green and Blue, (or perhaps Ruby, Sapphire, and Emerald) and the Prism and Pale Spheres corresponding to Diamond and Pearl respectively.
Spheres of these five colors can be found commonly by mining in the Underground. More common are those that are Red, Blue, and Green, while the Pale and Prism Spheres are common in the version that corresponds to them and rare in the other one. Spheres can range in size from 1 to 99, though most Spheres found will be in the range of 520.
To get larger Spheres, they can be combined by burying more than one of the same color Sphere in the same spot. When combined, the size of the resulting Sphere is determined by the following formula:
 X + (^{a}⁄_{5}+1) + (^{b}⁄_{5}+1) + (^{c}⁄_{5}+1)...
Unless the buried Sphere has grown at least once since a Sphere was added (or grown without a Sphere being added), in which case the formula is:
 B + X + (^{a}⁄_{5}+1) + (^{b}⁄_{5}+1) + (^{c}⁄_{5}+1)...
Where B is the size of a grown buried Sphere, X is the size of the otherwise largest Sphere buried, and a, b, c, and so on are the sizes of the other Spheres. All noninteger values are rounded down before the adding. In the event of a tie for the largest size, the largest Sphere size is used both as X and one of the other lowercase variables. For instance, burying a Prism Sphere 15, a Prism Sphere 12, a Prism Sphere 7, and two Prism Sphere 1s produces a Prism Sphere 22. Burying a Blue Sphere 15, Blue Sphere 3, Blue Sphere 22, on top of a Blue Sphere 3 that has grown by 2 yields a Blue Sphere 32.
Buried Spheres can also naturally grow over time. Red, Green, and Blue Spheres grow faster than Pale and Prism Spheres. Regardless of what a player does, though, the maximum level for a Sphere is 99. Additionally, only 99 Spheres can be buried at a time. Attempting to bury more causes the oldest Sphere to disappear. A Sphere Radar can be unlocked for a player's base, which can be used to help the player find the Spheres they've buried.
Spheres can be used to purchase many things that a player will need to decorate their Secret Base, as well as traps which can be set up throughout the underground. Hikers that stand at some of the corners of the Underground will offer to trade these items for the Spheres. The price that the item is listed for is the minimum size Sphere that the Hiker will take for it, though larger ones may be used.
Players are only allowed to carry a total of 40 Spheres of any size at any time. A full Sphere inventory will prevent the looting of any more Spheres, automatically 'deleting' any new Sphere that has been found in a mining session. If a player attempts to pull one of their buried Spheres from the ground, the game will report on the full inventory and refuse to do so, saying that the player has left it where it is.
Flavor text
 Red Sphere: A red sphere that glows like fire. It slowly grows when buried.
 Blue Sphere: A blue sphere that glistens like ice. It slowly glows when buried.
 Green Sphere: A green sphere glowing like sunlight in leaves. It slowly grows when buried.
 Prism Sphere: A crystal clear, hard sphere. It slowly grows when buried.
 Pale Sphere: A white sphere that glows in seven colors. It slowly grows when buried.
Appearance
In the anime
Spheres first appeared in The Grass Menagerie! in Team Rocket's fantasy. They later found a Red Sphere and loads more Spheres of other colors, giving them money for a meal.
In other languages

Red Sphere

Blue Sphere

Green Sphere
 
Prism Sphere

Pale Sphere

This item article is part of Project ItemDex, a Bulbapedia project that aims to write comprehensive articles on all items. 