Kael - Ahhh, the easy part! (Only kidding)
Now's the time to start bringing your A-Game! Bosses have a TON of HP and hit REALLY hard compared to MPG! Kael is simple (kinda). Kill 6 bosses, loot their items, and combine in your Universal Assembly Crate, then turn into Borat.
Recipe :: Progression: Mixed Bag of Opinions
You will need the following items:
Combine all 6 in your Universal Assembly Crate to create a Mixed Bag of Opinions!
Turn in the Mixed Bag of Opinions to Borat to receive your Perspective - Rk1.
To upgrade this you will need to combine two Epic Gemstone of Immortality in your Universal Assembly Crate to create a Perspective of an Immortal. Then combine 1 Perspective of an Immortal with your Perspective - Rk1 in your Universal Assembly Crate to get Perspective - Rk2. Continue upgrading that way until you get rk15, which is called A Great Perspective.