Crystal Sage
Maximum souls: 148,716
From the Road of Sacrifices bonfire, spam the Ring of Favor+3 to sprint to the Halfway Fortress bonfire. From here, equip the Silvercat Ring and jump off the cliff from the left-most edge. Keep to the left and sprint to the Crucifixion Woods bonfire. Have a fire weapon ready because a Starved Hound might chase after you. If you hit a Starved Hound with a fire weapon, it would stop to writhe on the ground to put out the fire on its body. Or use Hidden Body when you're near the Starved Hound. Light the Crucifixion Woods bonfire. You will need this bonfire later on to get to Farron Keep.
With experience, you can predict where the real Crystal Sage would spawn after teleporting away from you. Refer to this video for more details on predicting his spawn location:
Dark Souls 3 - Crystal Sage Guide on Sage Spawns and Crystal Patterns
The Crystal Sage is a magic spammer, but can easily be countered if you equip the Magic Stoneplate Ring+2, cast Great Magic Barrier, and consume a Blue Bug Pellet. Also cast Sacred Oath or use the weapon art of the Sunlight Straight Sword. Note that Deep Protection does not stack with Great Magic Barrier; casting one would cancel the other. The boss is weak against fire. My weapon of choice for this fight is a Chaos infused Lothric Knight Sword+10. A +10 straight sword, Sunlight Straight Sword+5, or the Sellsword Twinblades+10 buffed with Carthus Flame Arc should be more effective against the boss. Before buffing with Carthus Flame Arc, consider equipping these rings for bonus damage output: Lloyd's Sword Ring, Fire Clutch Ring, Witch's Ring. If you plan on spamming R1, or the 2-handed L1 in the case of the Sellsword Twinblades+10, consider equipping the Old Wolf Curved Sword and/or Pontiff's Right Eye. The following videos show strategies using the Lothric Knight Sword and the Sellsword Twinblades.
Crystal Sage NG+40 Lothric Knight Sword, Dark Souls III
Crystal Sage NG+32 Sellsword Twinblades, Dark Souls III
When you enter the boss arena, run straight to the boss. If you're lucky he would cast a purple variant of Homing Crystal Soulmass. If this sorcery is cast, you can be next to the boss, constantly strafe to your left, and R1 him. As long as there is one Soulmass hovering above the Sage's head, he would not teleport to a different location within the boss arena. In his second phase, the Sage would summon clones of himself. The true Sage is the one that uses purple magic; all other copies use blue magic. If you want, experiment with Chaos Bed Vestiges to see whether you're comfortable with a pyromancy strategy. Depending on how far you have progressed with Eygon's questline, you can summon him for jolly co-operation against Crystal Sage. Eygon is useful as a means of distracting some of the fake Crystal Sages during phase 2.
