To Bait a Forktail...
Main quest
Kaer Morhen suggested level 19 
On the world map
From the journal
Yennefer asked - or rather, if I am to be completely honest with you, dear reader, ordered - Geralt to help Eskel hunt a forktail. The sorceress needed ingredients from this dangerous beast's body and clearly thought two witchers would get the job done sooner than one. Geralt thus set out to track the monster - but first, he had to find Eskel.
In the end, the hunters bagged their prey. Using their traditional and, while we're being honest, rather unrefined methods, the two witchers first lured the forktail close, then wounded the beast and gave chase as it fled, finally finishing it off in its lair. And so they acquired the ingredients Yennefer needed and, no less important, had a bit of time to catch up - Eskel and Geralt had not seen each other in years.
