1. The Rusalka Quest in the Temple of the Snake. This one needs to be done first because you need the Horn of Ros (which used to be carried by Q, now by a Drow Dreamcaster). This horn opens the final door in:2. The "Save the Undead Virgins quest" in Kopienari (ex-Darkmoor). Once the final door is opened and all the ghosts and Daughters of the Dead have been killed, you will find the Pearl of Turmoil in a chest in the large room. This artifact is needed for:
3. The "Two Sisters quest" in Avalon and needs to be placed in a chest in the Castle on the hill just outside of Avalon near the stable. This is one half of that quest and the other half takes place at what used to be the Monolith also in Avalon. Fir the second half of that quest, you need to gather or make some ingredients, which if you don't want to bother with alchemy are also sold by Trader Joe in Abdul's Resort.