If you always wanted to know, how to level your Warlock without the Affliction Tree, then this Warlock Metamorphosis Leveling Guide is for you. The Demonology Tree is not only viable because of the mighty Felguard. Metamorphosis is a great way to level fast and I want to show you exactly how it’s done.
Many players underestimate the power of Metamorphosis because they just think of it only as an emergency ability to save their lives in tight situations. But the abilities you get while changing into your demon form are great to farm (quest)mobs.
One word of warning though: I do not recommend you to play with this leveling spec if you haven’t hit level 50 yet. The Demonology talents are great and make it easy to level your twink. But the early talents are just not as efficient as the later ones. So don’t use a talent build that relies on the Felguard and Metamorphosis if you can’t actually spec these talents!
Warlock Metamorphosis Leveling Guide – Talent Points

When it comes to the Warlock Metamorphosis leveling strategy, I think Destruction supplements Demonology way better than Affliction. You need to get gear with lots of additional spell damage and critical hit to get the most out of your Metamorphosis AoE spells.
Why not go all the way and get the matching Destruction talents?
Warlock Metamorphosis Leveling Guide – The Glyphs
Felguard – Increases your Felguard’s total attack power by 20%
Until you get the Metamorphosis spell – and even after that – you will rely on the Felguard to tank and kill most of the mobs. Major Glyph: Felguard is mandatory!
Metamorphosis – Increases the duration of your Metamorphosis by 6 sec
No need for an explanation here. Leveling your Warlock with the AoE farming ability of Metamorphosis simply requires this Glyph!
I hope you enjoyed my Warlock Metamorphosis Leveling Guide and have lots of fun leveling your character with the Demonology Tree.
