Silmaril

Reference

Link to Silmaril
Settings: many, including a variety of Ardas (the setting of the Silmarillion). Main templates: Bells and Maitimos, or Fëanorians more generally
Prerequisites:
All prerequisites are optional but contain helpful context. They are all readable standalone.
Luminosity & Radiance is quite long and worth reading first. Worm is also infamously long [NB: the creator of this reference hasn't read it]. The other prerequisites listed are not very long (longest is Eclipse) and can probably be read interspersed with Silmaril itself.

Subcontinuity

Prerequisite(s)

Map of known worlds
(made by phi)

Elentári

seidr and spear

-

Telperion

in which
the prime directive

-

Defy Your Limitations

Daevinity

-

North

Bindings

Map 0 (post North)

East

Luminosity & Radiance

Map 1 (post East)

Shine

Geode

Map 2 (post Shine)

West

groundhog day

Map 3 (post West)

South

-

Map 4 (post South)

Kandrona

-

Map 5 (post Kandrona)

Southwest

Eclipse

Map 6 (post Southwest)

untitled 1

-

Map 7 (post untitled 1)

Unbreakable Vow

the first page of either Bluebell Flames or Witchlight

-

untitled 2

-

Map 8 (post untitled 2)

Disappear

-

Map 9 (post Disappear)

shard

Worm

-

Starstone

-

-

Content warnings:
Authors did not use content warnings.
Silmaril contains:

characters being traumatized from having been tortured by evil gods
(the evil god torture is offscreen, mostly)
also a bit of regular, non-evil-god rape and domestic abuse (mainly in subcontinuity "Disappear")

Spoilers:Subcontinuity "West" contains major spoilers for Puella Magi Madoka Magica.