"They're here!"
Bai Xiaowen's expression sharpened.
The Territory Stele was a domain's most important control hub.
A lord had to use the stele to self-destruct a domain, scan the cosmos, or activate the Territory Formation.
Activating a cosmic scan through the stele cost Spirit Crystals. It was also like continuously broadcasting a signal—a searchlight in the dark. It made other domains easier to find, but it also made the scanning domain easier to detect.
That was why domains normally kept their cosmic scans off.
Even with the scan off, however, the stele could passively detect strong spatial disturbances within the same star sector.
And a disturbance that strong could mean only one thing: a Realm Gate!
A Realm Gate was a "transfer station" built at the cost of Spirit Crystals. Creating one was among a lord's powers and depended on the Territory Portal.
Compared with a Territory Portal, a Realm Gate was terribly inconvenient.
Building and maintaining one cost Spirit Crystals. Using one cost even more, and traveling through it took a considerable amount of time.
A Realm Gate was the fallback when a Territory Portal wasn't an option.
Generally, there were two reasons to build one.
The first was to explore a Cosmic Secret Realm. With no existing portal, a temporary Realm Gate had to be built.
The second was what was happening now—a war of territorial conquest!
Great Tang Domain had already scanned and obtained White Phoenix Fief's Territory Coordinates.
In peacetime, Great Tang Domain could have used those coordinates to request passage through White Phoenix Fief's Territory Portal and appeared directly inside the domain. But they were at war. Bai Xiaowen would never grant that request, and Great Tang Domain wasn't foolish enough to bother asking.
Instead, Great Tang Domain had gone to great lengths to build