Sage’s Cave is an Elden Ring side dungeon found on the western side of the Altus Plateau region and the home of the two bosses: Necromancer Garris and the Black Knife Assassin. The Sage’s Cave, while being a small dungeon, provides a lot of loot for you to collect, well hidden behind illusory walls.
Therefore, in this guide, we will help you fully discover Sage’s Cave in the video game developed by FromSoftware for PC, Xbox, and PlayStation.
Where To Find Sage’s Cave
Sage’s Cave is located on the Altus Plateau’s western cliffs, south of the Wyndham Ruins.
To reach Sage’s Cave dungeon, first visit the Abandoned Coffin Site of Grace, located on the western edge of the Altus Plateau region. Head north along the small lake’s eastern shore. The cave entrance is hidden behind the trees.
Once inside, continue forward past the Site of Grace until you reach an apparent dead end. This is an illusory wall that you need to hit once to reveal the rest of the dungeon. Head forward until you come across a skeleton by a waterfall. Once you defeat the skeleton, there is another illusory wall to the right.
Behind this wall, you will find two chests on a wooden platform containing Lost Ashes of War and 5 x Rejuvenating Boluses.
Following the path down, you will find two corpses, each holding a Golden Rune  and 5 x Silver Firefly to gather. There is another illusory wall to your left with four skeletons and four chests behind it.
After defeating the four skeletons, you can open the chests to receive 5 x Silver-pickled Fowl Foot, Black Hood, Candletree Wooden Shield, and a Nascent Butterfly.
Head through the tunnel to reach the next room, where you will find four more skeletons, one of them wields a giant halberd and has more health than the others.
One of the skeletons faces an illusory wall, hiding a chest containing a Stonesword Key. The next room contains three more chests holding 10 x Golden Greatarrow, Raptor Talons, and 4 x Dragonwound Grease.
Continue through the tunnel until you reach an open cave with a waterfall, then jump to the left and hug the left wall until you reach an apparent dead-end.
Hit the illusory wall to reveal two more chests containing Raptor’s Black Feathers and Skeletal Mask. There is another illusory wall on the opposite side of the room that reveals the Necromancer Garris Boss chamber.
Garris is a necromantic sorcerer that summons flying skeleton skulls to attack you. His most powerful spell conjures a giant skull that strikes you as it rolls around the arena.
To make this fight easy for yourself, you must first defeat this giant skull. Garris doesn’t have a large health pool; therefore, you should be able to defeat him quickly.
You’ll be rewarded with the Family Heads Flail when you finally defeat him. Return to the waterfall and take the left path. It will bring you down a slope with a mist wall at the bottom, where it will be the main boss of Sage’s Cave, the Black Knife Assassin.
The Black Knife Assassin will be invisible during this boss fight. As a result, you won’t be able to see the Black Knife Assassin at all during the fight. The only way to see the assassin in this fight is to buy a Sentry’s Torch for 7000 Runes from the Hermit Merchant and equip it in your off-hand to make the assassin visible.
This fight will be a piece of cake if you use the Mimic Tear Spirit Ash. After defeating the Black Knife Assassin, you’ll receive the 9000 Runes and the Concealing Vein Talisman.