This short guide will explain the mechanic of Sephiroth system.
Guide to Sephiroth System
At its basic form, it works like this: any castle or warrior camp now has elemental affinities
So, if you play a Rune of Embers on a castle, it will get one level of Fire, giving you the favour of the Fire Sephiroth.
Each castle can go only to four levels of affinity max and the current level is displayed on the castle with the element icons.
You can see the global affinities level near the corrution meter, each five levels give you a nice reward as long as you can keep up the Sephiroth’s favour!
They affect both you and ORX, so it’s a risk-reward kinda thing.
The ORX can also have these affinities. For example the ORX clan devoted to Earth Sephiroth will deal more damage to castles with Wind affinities, but at the same time they’ll receive more damage from Fire castles.