The Heartcoal

The star's core, nine hundred feet down in the trench at the centre of the isles, still glowing. On a calm night, fishermen over the trench see a faint blue light far below the boat, and row away without a word.

The Ilvaric Vigil calls it the heart of Ilvara. The Choir of Fathoms calls it the splinter in Morrow's side. The Aurel Combine calls it the only cindrel that never dims, and means to raise it. The Wickwardens believe waking it is what drew the Sallowkin in the first place, and the Slackwater want exactly that.

No one in the starter arc goes there. Everyone in it is fighting about it.