Frost Scythe

Each enemy hit increases your attack speed by 1% for 5 seconds. Max 15 stacks.

Grim Scythe's damage turns into Cold.

Unlocked at level 45

Unstable Compound

Each cast increases the radius of your next Nova by 5 yards up to 2 times.

Unlocked at level 18

Devouring Aura

Becomes an aura that consumes all corpses within 15 yards to restore 11 Essence per corpse.

The range of this effect is increased by 50% of your gold pickup radius.

Unlocked at level 38

Aura of Frailty

Becomes an aura that curses all enemies within 15 yards.

The range of this effect is increased by 50% of your gold pickup radius.

Unlocked at level 39

Harvest of Anguish

Bone Armor also increases your movement speed by 1% for each enemy hit.

Bone Armor's damage is turned into Cold.

Unlocked at level 48

Potency

Increases your armor by 100% for 2 seconds after casting.

Unlocked at level 34