Seekers are players of the futuristic MMO CrossWorlds around which CrossCode is based.
A Seeker is a human who has undergone special training and been allowed access to the Track of the Ancients. Once they choose one of the 5 Virtues, their goal is to master all 4 elements and use them in a final challenge to solve the mysteries behind the track.
In CrossWorlds Lore
Seekers are humans who have been trained and selected one of the 5 Virtues so that they can interact with the Track of the Ancients. This allows them to follow the Track, collecting the four Elements and ultimately gaining access to the Secret of the Ancients.
The connection between Seekers and the Track also renders their assistance invaluable whenever inhabitants of Shadoon try to use the Track or are inconvenienced by it. This is typically done through the Factions offering Quests for Seekers to complete.
Players of CrossWorlds take on the role of a Seeker, and, guided by Operation Trackwalker, follow the Track of the Ancients. Almost all Avatars seen in CrossCode, including Lea, are CrossWorlds players and therefore Seekers.