In order to grab this skill point piece you need to enter Pothole Cavern – public dungeon. There is a camp of Shadowed Path enemies defending its entrance, as well as cave inside. Group of 2 mobs are regular. Patrolling creatures sometimes join this groups. Skyshard you are looking for is inside the largest Pothole Cavern room. It is on top of a small stone shrine, next to candles. This is a possible spawn area of Serrin Vol. He is a pretty tough mob to solo. In order to defeat him you need to annul his powerful instant spell. This spell is devastating and you need to find a way to survive it. He also spawns an add that helps him in combat. Another prize for defeating Serrin Vol comes in a shape of lorebook “On the Detachment of the Sheath”. This lorebook is in the same area where you can collect the skyshard.
At The End Of A Bumpy Road Skyshard
Guide:
Southern Cyrodiil, between Castle Black Boot (to the southwest) and Castle Faregyl (to the northeast).
