The Roving Threats have been a fun addition for raiding for level 100's or near to that level.
The quests may be picked up in Eriador in Angmar in a tent near the reflecting pool, Forochel not far from the stable at Suri-kyla, Misty Mountains near Gloin's first camp by the task board. The Epilogue baddie is marked . The Gondor hub can be picked up in West Gondor at Dol Amroth nearish the stairs from Aelnir, and Central Gondor at each of the three main stable towns. Reputation is needed.
The Threats aren't currently marked on the map so here's a link that helps find them, from the Department of Strategy: