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From Pathfinder Impossible Magic, which isn't enabled.

Ouroboros Flail

ITEM 14
Price 4400 gp
Usage held in 2 hands
Bulk 2
Category martial
Group flail
Damage 1d10 bludgeoning

You can easily magically expand and contract the chain of this +2 greater striking extending war flail.


Activate—Chained Grasp (concentrate)
Frequency once per hour
Trigger You successfully Strike with the ouroboros flail as part of activating its extending rune
Effect The head of the flail wraps around the target of the triggering Strike and drags it in your direction. The target must succeed at a DC 32 Fortitude save or be pulled adjacent to you. A creature pulled to you is then Grabbed by the flail until the end of your next turn unless you move, your target Escapes, or you attack with the flail, whichever comes first.

Activate—Infinite Links (manipulate)
Effect You extend the flail's chain, then wrap it across itself and strike two links together. This severs up to a 60-foot loop of usable chain from the flail, which instantly returns to its normal length. If you use Infinite Links again, any previous chain you created with it disappears after 1 round. As with most obviously magical and temporary constructs, the chain can't be sold.
Pathfinder Impossible MagicORC