Rift Shard

A Rift Shard is a piece of matter from the Outer Plane. Rift Shards are composed of exotic matter which can not be fully described or quantified, as they originate from a higher order of universe than our own.

Origin
After The Gardener was struck by Sorrow, The Bog formed a connection between the Inner and Outer Planes, allowing Rift Shards to enter the universe.

Connection with Time
Time is a force which moves Rift Shards closer to each other. This force is not exerted solely on the Shards themselves, but anything which obstructs the motion of the Shards on their route. A shard cannot ambulate or move on its own in anyway, but the flow of time seems to help them along on their path.

Connection with the Gardener
Rift Shards are thought to be pieces of the Gardener itself. A common analogy is platelets in the human bloodstream, moving through the body until the reach an open wound. The Rift Shards movements through the universe have been likened to this healing process, and some believe the Bog will be sealed and the Gardener will awaken when the process completes.