Valheim Seekers are the new insect-like creatures that are only found in the Mistlands biome. There are two different varieties, one of which has wings and can fly short distances, which can easily catch your Viking unaware. Thankfully, this variety tends to stay on the ground for the most part so you have a better chance of seeing them coming.
These enemies are often found in pairs so you'll need to be on your toes if you hope to survive exploring the new biome. Knowing the Valheim Seeker's weakness is essential if you want to beat them, so I'll explain what you need to know to make your Mistlands adventures less deadly.
Valheim Seeker weakness: How to defeat them
Valheim boss (opens in new tab): Summon and defeat them all
Valheim workbench (opens in new tab): How to build and upgrade it
Valheim dedicated server (opens in new tab): How to get one working
Valheim commands (opens in new tab): Handy cheat codes
Valheim mods (opens in new tab): The best player-made additions
If you try taking on a Seeker head-on, you'll soon find they don't take much physical damage. You can parry their attacks, but the damage you do in return isn't great. Your best bet is to get behind them and attack them from there, though you'll need to try to avoid their legs to hit the abdomen.
They have some weakness to elemental damage so the Staff of Embers (opens in new tab) or the frost staff will be really useful here. If you don't have access to magic yet, the Frostner hammer is an okay alternative, and will also help by slowing them down, potentially making them easier to deal with.
It's possible to poison them, too. The feather cape (opens in new tab) is also recommended as some of their attacks have a big knockback, and as the Mistlands has a lot of treacherous drops, you don't want to fall to your death while fighting.
What do Seekers drop that makes them worth fighting? Both types drop Carapace, used to make the Mistlands level armor, and Seeker Meat which can be used in several Valheim food (opens in new tab) recipes. The Seeker Soldier—the non-winged variety—will also drop a Mandible, which can be used to craft two of the new weapons. Both also have a chance to drop their respective trophies.