Gummi Blocks

Gummi Blocks are essentially portable blocks of elastic material that have properties attached to them. They can be utilized in one form to create Gummi Ships, which are necessary to travel from world to world. Blocks can be found in chests, dropped from fallen enemies and ships and even purchased when Pinocchio and Gepetto are in Traverse Town. They can also be bought from Cid who eventually proves to be an expert in Gummi engineering and helps when Sora finds half of a Navi-G block in Deep Jungle.

A basic understanding of what Gummi blocks are can be inferred from the Ansem Reports. It appears that when Heartless appear, or when the door leading to a world's heart is opened, the wall that protects that world collapses. Gummi blocks then appear in said world, as in the case of Ansem's study of the meteors, suggesting that the blocks are remnants of the protective wall of the world. This would account for them appearing in many shapes and forms and bonding easily with each other. It is possible that Gummi is also present in between worlds, which might explain the presence of so many Heartless Gummi ships. The nature and origin of Gummi blocks allows them to travel to other worlds.

As mentioned in the Ansem Reports, Gummi blocks are "elastic" and "bond easily" when combined, as evident when creating Gummi Ships. The blocks themselves are very numerous and come in all shapes and sizes with properties attached to each. When added to Gummi ships, they provide advantages such as improved armor, increased acceleration and greater firepower. In both versions of Kingdom Hearts, specialized Gummi blocks can be used for other advantages, such as warp travel in Kingdom Hearts.