Cooperative boss victories provide a repeatable way to earn Rune Arcs for activating an equipped Great Rune.
PC / Global, base game plus Shadow of the Erdtree expansion
WHERE & HOW TO FARM
Where to farm
Summon pools and boss fogs where other players can summon your cooperative sign in the Lands Between.
When you help another player defeat a boss as a summoned cooperator, a successful completion rewards a Rune Arc. That makes co-op a renewable route, though it depends on finding a host and surviving the encounter. Rune Arcs are consumed when used and activate the Great Rune you have equipped, so first restore a rune at its Divine Tower and equip it at a grace. This method works in the base game’s multiplayer and requires an online connection.
Online access and multiplayer enabled for your platform and account.
A Furlcalling Finger Remedy to see summon signs, or a Tarnished’s Furled Finger to place your own sign.
A boss encounter your character can handle at the host’s progression level.
Choose a boss you have already reached or can reliably fight as a cooperator.
Use a Furlcalling Finger Remedy to look for a summon sign, or place your own sign with a Furled Finger.
Join the host’s world and stay close enough to participate in the boss fight.
Avoid taking unnecessary risks; the co-op reward requires the host’s boss to be defeated.
On success, confirm the Rune Arc reward and return to your own world.
Use the Arc from inventory when your restored and equipped Great Rune is worth activating.
Farming tips
A familiar boss gives you a better chance to survive and complete the host’s fight.
If signs are scarce, try a different active boss area or place your sign where players are progressing.
Repeat, collect and use
Repeat successful co-op boss assists as often as suitable hosts and encounters are available; each victory can yield another Rune Arc.
Common mistakes
Expecting an Arc for an unsuccessful attempt: only a completed boss victory provides the reward.
Entering without a useful Great Rune equipped: restore and equip one first if you plan to spend the Arc.
Treating co-op availability as guaranteed: switch to exploration or merchant stock when matchmaking is slow.
When to stop or switch
Stop when you have enough Arcs for the next difficult section, or change to exploration and limited merchant stock if the required boss area is inactive.
