Non-EG lore

[Gann the Derpimann]

What are all the things that are canon to OA but not mentioned in EG? For example the Deep Night Runners, Trapdoor Spiders, etc.

These are all technically 'meta-canon' rather than hard canon (so YMMV), but anyway. Besides those two, there are:

a) The Meistersingers are actually the HEEC-2 civilization surrounding the galactic core.

b) The Meistersingers used the Prime Radiant super-weylforge surrounding the galactic core black hole to access 103 galaxies and expand their civ to them. The wormhole links to those galaxies were already in the Prime Radiant when it was discovered. Since then the Meistersingers have used the PR to create wormhole links all over the portion of their civ in the Milky Way and other parts of the MW galaxy.

c) The Meistersingers currently only occupy 102 galaxies. When a faction of their civ operating in the 103rd galaxy attempted to interfere with the Deep Night Runners, the wormhole link to that galaxy disappeared. Some millions of years later, the light from that galaxy arrived at their next nearest outpost and showed that the entire galaxy had disappeared in that same moment. The Meistersingers were suitably terrified.

d) The Leviathan's name in the language of its builders translates as Habitat Node 12. There are actually 14 Leviathans spread across the universe, all linked by wormholes - so essentially a single universe spanning mobile structure with a mass greater than a trillion suns. Very little of the mass of each Leviathan consists of either stars or dysons.

e) The purpose of the Leviathan is to bring as many civilizations as possible into itself where they can interact and develop together without the issue of intergalactic space keeping them apart.

I think that about covers it - at least for the stuff I'm familiar with.

Todd

Are the galaxies that the Meistersingers occupy close to each other, and do they occupy the other galaxies in the local group? Also, in this article: https://orionsarm.com/eg-article/4be587099881e
It says that the 3 of the HEECs may actually be the Meistersingers and that the Meistersingers have made contact with the Leviathan. Is this true or is it just Terragen speculation?