Armageddon Hail (R1) - Armaggedon now spawns 3 smaller meteors to fall in a random area around the main meteor. These smaller meteors to 300 damage to anyone hit and release a smaller fel shock wave that deals 600 damage to anyone hit by the wave.
Kil'Jaeden's Cunning (R2) - Mind Invasion spreads to all enemy heroes damaged or healed by the original target. Now lasts for 30 seconds or until Kil'Jaeden is killed
Chaos Bolt Volley (W) - When Chaos bolt hits an enemy hero it now bounces to any nearby enemy heroes
Soul Harvester (E) - Kil'Jaeden now fully rips the heroes soul from their body. The soul now transfers 100% of the damage taken back to the hero and if the soul dies, the hero dies. Kil'Jaeden rips the soul with so much force that it pulls the soul over to him. However, because it Kil'Jaeden is now the only one able to damage the soul.
Wings of Destruction (Z) - Kil'Jaeden can now cast abilities while mounted. Adds a 15 second cooldown to mounting
Heroes of the Storm Build Guides
[Fel Claws] making the target take 20% more damage for 5 seconds would be overpowered by itself, but it also Slows them, makes your next Basic Attack instant, and doubles its damage. This is just too much value, even for a 20 second cooldown.
[Focused Dreadflame] deals too much damage. Simple as that.
[Chaos Bolt] deals TOO much damage even if it does move slow. It is already diffuclt to block due to it ignoring most enemy units.
[Shadow Reflection] sounds like a cool idea, but is a very broken effect, as it is basically free damage on any target without any counterplay.
[Nether Gale] is simply overpowered. It almost doubles his Health for the duration.
[Armageddon] sounds almost identical to Ragnaros's [Sulfuras Smash]. It is also extremely overtuned in terms of damage.
[Mind Invasion] sounds extremely frustrating to play against for most characters.
Can [Flight] not be interrupted at all? Is there no cooldown?
Fel claws does have a lot of value baked into baseline. Design wise I do think that is a problem the more I've thought about it. A good portion of the power should be baked into talents
Shadow reflection is an interesting one to design weaknesses, consistency, and counter play into it. I believe it would require a lot of play testing to make it healthy, whether those final changes would be number related, spawn logic related, or making it so only KJ can damage it.
Other than number changes, I believe I would make Nether gale a talent at 16 instead of a baseline ability.
I did have a problem with Armageddon when I was making it, with that it was too similar to Sulfuras Smash, which is where I ended up giving it the shockwave. It is the part of the concept that I am the least comfortable with because of that. It was such an infamous ability from his Legion fight that I wanted it included but making it faithful to the fight would be so frustrating to play against and making it more suitable for HOTS makes it so similar to Sulfuras Smash
I get the concern about Mind Invasion. My favorite hero is li-ming and my favorite build is Q, getting hit with that ult would drive me insane. A tweak I would make would be that only the heroes ult is impacted.
I would have flight be interruptible during the cast. I would keep the cooldown the same as other mounts, unless you take the level 20 upgrade where I would add a larger cooldown to it.