Spoiler: this describes a guardian and its moves.

The Unmoving
Chapter: The Stillness
Who stopped the world? He waits in the Founder's Hall under the glass of the Dead Calm — the Eye of the Hour finds the Hall. Read a riverbed sluice in the Hall or the dais itself with the Loupe.
How to open it
- Read with the Loupe: Riverbed Sluice or Founder's Dais or
unmovingor - Notes: The Stillness — 8
- After the entries:
The Great Pendulum - Dissonance for study: 3
Pages of the entry
1
Defeating the Unmoving gives the Heart of the Stilling, the key to the Restart, and a Hubstone of five spokes. The Founder's Hall lies under the glass of the Dead Calm; its gate opens to the Pendulum Bob set in the dead clock above it. Bring four Thaw Lanterns and shards of the four Springs: a lantern and a shard in a riverbed sluice, and the riverbed flows. He moves only while you move: freeze, and so does he.