NOTE: If you wipe before you kill Morphon, you will have to restart and grab all the memories again to open the Vex gate in the jumping puzzle. Make sure after you kill Morphon that you DO NOT scan Praedyth's body, it will end the mission.
Daily Heroic Mission - Paradox
Full disclose: This only gets you missing Grimoire score and cards and a ghost to get rep from FWC. It may be a trigger to another questline, but nothing is proven yet.
Mystery: The Vault of Glass
This can be found when you take the secret path in the Paradox mission inside the Vault of Glass. Where there's an open area to your right before the doorway with the malfunctioning Vex, you can drop off the ledge to the secret path in Trials of Kabr. Take the path until you see the first red light, and on the right in a corner will be the dead ghost/memory.
Mystery: The Vault of Glass 2
This can be found when you take the spirit bloom path in the Paradox mission inside the Vault of Glass. To get to the path, after you hit the Templar's Well and clear out all the Taken, on the very left of the area before the stairs/incline, there's a whole in the wall you can jump in. Continue down the path past the first area with lights, and you will then approach a pillar with a light in it that has a ledge you can jump on top of. Jump up here and before the next drop down, in the corner the ghost will be there.
Mystery: The Vault of Glass 3
This can be found after you defeat the boss and head to the traditional jumping puzzle in the Vault of Glass. To get to this path, turn around from where the skeleton is and hug the right. After you exit the room and head into the big open area, hug the large wall on your left. Keep hugging this wall as it curves around to the right and there will be a hole in the wall. Follow the path and it will take you to the jumping puzzle in the area "Vault of Glass". You head up to the left in the cave, and circle around in it until you reach the ledge. From there you drop down to your right and there will be a little platform you can land on underneath you. Turn around and the ghost will be in the cave connected to the platform. I defeated the boss prior to going here, not sure if necessary however.
You need to obtain all 3 in order without dying for them all to appear. If you die the first one will respawn and you need to obtain it again in 1-2-3. After this it will trigger the portal to Praedyth's Door where you can fight the ultra and get the Cult Ghost.