Ancient Leshen

An ancient leshen is a leshen that has lived long enough to grow far stronger than its kin. Like any leshen it is a forest relict that rules its woods through the animals living there. Wolves fight for it and crows and ravens circle where it hunts. The oldest ones have learned the art of marking: they plant a piece of their essence in a person living nearby, so that if the leshen is killed it can be reborn near its lair.

Some communities treat such a creature as a guardian spirit and make pacts with it. In Skellige, the elders of Fayrlund worship the Woodland Spirit as a protector, even as it kills villagers who stray into its woods.

In The Witcher 3 you can face that ancient leshen in In the Heart of the Woods in the Skellige Isles. Siding with Sven means finding the marked villager, smashing three totems and killing it. Siding with Harald renews the pact instead, and you miss the ancient leshen mutagen and the Woodland Spirit achievement. Hearts of Stone gives you another chance: an ancient leshen and a pack of wolves guard the Arnskrone Castle Ruins in Deadwight Wood, where the treasure hunts The Secret Life of Count Romilly and A Dark Legacy lead you.

Combat strategy

An ancient leshen rarely fights alone. Wolves come with it, and they keep you busy while it lashes out from a distance. Clear the wolves first, then turn to the leshen itself. Fire is your best weapon: set it alight as often as you can, because a burning leshen gives you room to hit it. When it vanishes in a cloud of smoke or crows, use that moment to throw a bomb.

In Fayrlund, deal with the marked villager before the fight, or the leshen will just come back.

Coat your silver sword with Relict Oil.
Use Igni over and over to burn it and open it up for attacks.
Dragon’s Dream and Dancing Star are good for setting it on fire, and a Dimeritium Bomb also works against it.
Keep Quen up for the hits you can’t dodge.
In In the Heart of the Woods, the totems are enemies too. Destroy them without waiting to clear every wolf.