Under breakable crates/barrels in the bottom of the tower that you go through to exit the Siegeward/Fire Demon area in Undead Settlement.ДЇrom the Pontiff Sulyvahn bonfire, backtrack through the initial entrance and drop off a ledge straight ahead to land on a structure below. The ring is on a corpse behind some crow enemies. Proceed from the Untended Graves bonfire and take left path. Can be found in NG+.Д«ehind the large throne in Dark Firelink in the Untended Graves.ДЇound in Gwynevere's Chamber above the Aldrich, Devourer of Gods bonfire.ДЇound behind the locked door on the left side of Firelink Shrine accessible by going through the locked door on the right side of the area (which requires the Tower Key from the Handmaid to unlock) and dropping down via coffins sticking out of the wall. Once outside, head around to the right and look for the ring on a ledge below. Climb a ladder and then exit through the door on the left. On a Ledge where you meet Siegward in the Undead Settlement that is accessed by jumping off the lift before it reaches the top.ДЇrom the Dragon Barracks bonfire, cross the bridge and enter the room on the right. These can be found on a corpse behind an illusory wall near the Old Wolf of Farron bonfire. Starting gift or sold by the Handamaid in Firelink Shrine after returning the Dreamchaser's Ashes. Rings can be traded between players, so if you have a friend that has a ring that you're missing and they drop it for you, it will count towards the achievement.

Some are are only available as covenant rewards and can't be obtained otherwise. Most are found in static places throughout the world. In subsequent playthroughs, all of the rings from previous playthroughs are available as well, so you can't miss out on anything that you didn't get by going to the next playthrough. The +2 versions (and single +3 version) can be found in playthrough 3 (again, in unique locations). The +1 versions can be found in playthrough 2 (in unique locations). The basic versions of each ring can be found in the first playthrough. Any that appear more than once have multiple versions that can be found in subsequent playthroughs. This image shows inventory order for all rings.

Therefore you need all 70 basic rings AND all +1 and +2 versions (one ring has a +3 version, too). This achievement requires collecting all 107 rings, which includes all variations.

Dark souls 2 wolf ring