Indra currently is the main Realm of the Sylphe Project. It is a vanilla 1.13.2 server running on Spigot. It was hosted by Zebeth under the name Brinstar for a limited time as Osenia required Weyard to run. It was then moved back to Weyard as its popularity increased.
Brinstar, as well as each active Realm, is locally archived each hour for the last 48 hours. That way it can be reverted in case of griefing or data corruption. On top of that, a copy of the latest backup is sent to Neudaiz so that if the disk crashes on Weyard, an emergency replacement Realm can be created immediately.