War Resources

War Resources are Battle for Azeroth's iteration of Garrison Resources and Order Resources. They have a variety of uses, including recruiting troops, running missions, and researching upgrades, as well as being used to unlock new outposts and outpost upgrades. It is possible to transfer War Resources from one character to another, but at a fairly significant loss.

Source
Looted from rare mobs/treasures, or rewarded from various quests.