Complete Lae's Hollowborn Paladin quests from /hollowdeep. Each quest requires the reward of the previous quest to accept. The third quest requires the Ascended Light of Destiny too (check Requirements).
Complete "Experiment 231: Sparrow Blood Potion" from Reens at /arcangrove. If you don't know how to get to her, go up into the tower then walk into the blue portal at the bottom-right. To complete the quest, defeat Gorillaphants and Seed Spitters at the bottom and bottom-right of the overall map as there are 2-3 of each on either screen.
You should still have the Blinding Mace of Destiny from farming BLoD (check your bank). Use it to complete Artix's "Finding Fragments with Blinding Mace" quest from /necropolis by defeating enemies at /battleunderb.
Dark Arts Scholar
Purchase from Artix's DoomWood II Rep shop at /necropolis.
Gem of Superiority
Defeat Legion enemies at /shadowblast (from the starting room, walk up, left, up).
Exalted Paladin Seal
Purchase from Artix's Rep shop at /darkthronehub for 500k Gold.
Defeat the Unending Avatar at /timevoid (select Timevoid from Braeus' Fast Travel at /shadowfall).
Human Soul x200
Defeat Lightguard Casters and Paladins at /noxustower (walk left to find them). If you haven't completed the storyline, walk until you reach the gate to find 2 Lightguards and the Wolf, otherwise, keep walking past the gate to find 3 Lightguards.