Deathwing by Indydude7

Whenever your health falls below 60%, you are surrounded by an expanding pool of magma. The pool expands slowly (up to slightly more than Arthas' Frozen Tempest radius) for every 1 second  that you remain below 60% health, and deals 75 (+4% per level) damage per second to enemies that stand in it. Quickly recedes when you regain health.

A wall of molten rock erupts from the ground, knocking back enemies in the way. The wall then recedes, leaving behind a line of magma for 3 seconds, dealing 90 (+4% per level) damage per second to enemies that stand in it. (Uses vector targeting)
Mana: 80
Cooldown: 13 seconds

Choose a small point on the ground (Spectral Scythe size) to transform into magma, which enemies will sink into and become rooted after 0.5 seconds. 0.5 seconds later, they are then pulled a short distance towards you in a straight line and take 65 (+4% per level) damage.

Mana: 65
Cooldown: 8 seconds

Activate to gain 25 Physical Armor for 4 seconds. Basic Attacks made against you extend the duration by 1 second.

Mana: 40
Cooldown: 10 seconds

Summon four pillars of stone at cardinal points around a large area. After a 1 second delay, the pillars converge, pushing any enemies caught between them to the center, stunning them for 0.5 seconds and dealing 180 (+4% per level) damage.

Mana: 80
Cooldown: 70 seconds

Transform into a dragon. While in this form you gain 10 armor, and an area in a large radius around you is filled with tremors, slowing enemy movement speed by 50%. Your own movement speed is reduced by 20%. Lasts 16 seconds.

Mana: 100
Cooldown: 90 seconds

Summon your dragon wings (dripping with magma) and fly low to the ground.