Stage 1: When you first load in, go straight for the 4 Shadow Mages, located on each side on the arena. Try to kill them as quickly as possible to avoid any more Shadow Minions from being summoned. The fastest way to kill these mages is with the Zephyr Rune, if you have it it's potentially the best rune of this raid.

Stage 3: Once the Shadow Warlock is defeated, he will cast a curse, now you are no longer able to use support skills for the rest of the raid. After a 10 second dialogue session, Sun's Shadow will have spawned. Try to save a lot of HP before fighting him as one of the moves seems to be undodgeable. You need to have good dodging skills to avoid his attacks. Use Flame's Acceleration Divider and Shatter to deal massive amount of damage, alternatively, you can use Snow Angel/Holy Light's Heavenly Splitter and Piercing Strike to take him down.

Shadovis RPG Script  Kill Aura, Fast Skills ...