The Shardspace is a dimension full of fractal dark-red crystals that are borderline incomprehensible to the human mind. The crystals glow dimly.
It is at least a semi-virtual space where real distances are inconsistent with distance traveled. How much of it is physical, and the degree of interaction with the real physical space is questionable.
The Shardspace is divided into islands over bottomless darkness. Each island represents a specific shard and its host, and houses Endbringer-like shard-avatars. Islands can be merged or bridged by power interactions in real-space. Presumably, the crystals forming each individual island is the real body of a shard.
The space between distinct islands is filled with un-distinct connective tissue, which can be claimed by individual shards or several. After Zions's death those claims became chaotic and overburdening, leading to mechanical conditions that produced Broken Triggers and Titans.
Interaction with ParahumansEdit
When a group of capes entered the shardspace through a dream room of the Mall Cluster, they were de-powered and constantly sent out visible pings of light to the avatars of their agents. The intensity of pings seems to vary depending on distance or their mental state. The hosts and agent-avatars, presumably, can voluntarily merge when nearby.
The hosts are also semi-immortal while inside the shardspace, since they always can get a new, memory-based "body" from the crystal surface. However, fatal wounds still can sever the connection and render them brain-dead in the real space.
After reality broke, cracks opened into the world that allowed anyone to enter the shardspace. When entered this way, the capes in question retained some of their abilities, though they become significantly weaker, the further they are from the conventional reality. The Wardens deployed artificial portals to provide power-support for their capes forced to act inside the Firmament.
Notable Residents Edit
Suffered extensive, but unspecified damage, that impedes its functions since that event.
Post-Time Bubble PopEdit
Teacher had uncovered a portal to the shardspace.
Breakthrough alongside Tattletale, Decadent, Syndicate, Chicken Little, Love Lost, Colt, and Damsel of Distress III broke into the Shardspace through the Mall Clusters dream room. There, they witnessed several shard entities including Grasping Self and others from the Mall Cluster, several shard entities from members of the Taught, Tattletale's shard, the Wretch, and Teacher's shard entity itself.
Ten patrol officers with dormant Corona Pollentias, including Gilpatrick, were tinker-linked by Lookout to Rain, allowing them to invade the virtual side of The Firmament. Two of the officers were impersonated by Matryoshka and Bijou.
On Victoria Dallon's advice the Wardens organize a mass incursion into the Shardspace. It instantly agitates the nearby Titans,  and Ziz The sabotage succeeded in temporarily weakening Titans.
- Black and red are common as colors of power manifestations in the story. A lot of villains also favor those colors in their costumes. It may be that this aesthetic is a default influence of shards in some form.