Mephisto by varkarrus

Level 1:

Invigorating Hatred: Attacking a target marked with Hatred will cause you to heal 45+4% health over 1 second.

Evil Vigor: Corrupted Zone healing increased by 30%

Dark Priests: Zakarum Councilman will heal every 3 seconds instead of 5.

Level 4:

Dark Expanse: Corrupt Nodes have 25% increased radius

Recharge: Casting Lightning Wave and hitting at least one enemy hero will heal 10% of your health.

Charged Bolt: Casting Lightning Wave will also shoot 4 charged bolts that spread out in a cone, dealing equal damage to a single target each.

Unholy War: Allies attacking a target marked with Hatred gain 15% bonus speed for 1 second.

Level 7:

Misanthropy: All enemies marked with Hatred gain an immolation aura that deals 85 (40+4%) damage per second to their allies. Enemies can only be damaged by one such aura at a time.

Static Charge: Enemy heroes hit with Lightning Wave will fire a single charged bolt at an enemy hero within melee range, dealing no damage, but rooting them for 1 second. Two heroes can root each other in this way.

Brink of Death: Zakarum Councilman heal an additional 5% of allies missing HP.

Level 10:

Spur Onwards

Infernal Gate

Level 13:

Territoriality: Seething Hatred's attack speed boost is increased to 45% if the enemy is in a corrupted zone.

Die For Me: Whenever an allied minion in a corrupted zone dies, it heals all nearby allied heroes for 45+4% health.

Deep Fog: Enemies that spend more than 20 seconds in a corrupted zone lose 20% attack speed until they leave.

Level 16:

Maffer's Might: Zakarum Councilmen will charge towards their targets, and their attacks cleave for 50% damage to nearby enemies.

Toorc's Frost: Zakarum Councilmen's attacks slow by 30% for 3 seconds.

Lightning Storm: Lightning Wave has 50% increased width and range.

Level 20:

Mass Hatred: You can cast Spur Onwards a third time.

Hell Portal: Casting Infernal Gate creates a second one inside your Altar of Storms. Allies can travel between them at will, taking 3 seconds to do so.

Legions of the Damned: Casting Council of Zakarum also spawns 5 flesh crawlers.

Encroaching Darkness: Corrupted Nodes last for an additional 90 seconds