It's the same thing with any Forsaken "army", the event is enabled even if you've never seen them.

the game is unfathomably hard you need to watch it, ive got 773 hours on this game and its always been an endless death loop. stop telling them to make it harder, instead encourage them to add a dificulty button so we can both be happy.

According to https://valheim.fandom.com/wiki/Events "They sought you out" is enabled by killing Yagluth, and disabled by killing The Queen.

Additionally, the raid cannot spawn seekers or seeker brood with stars; the little yellow ones you were one-shotting can be one-shotted with a level 1 club, and the larger ones (the actual seekers) only had a health pool in between a no-star and a one-star Greydwarf Brute.

Seekers with stars are much tougher. Good luck in the Mistlands!

there were seeker with health pool and brood but no stars. the seeker i fought were just stupid and never tried to break my walls