Details on Kael'thas' ults:
https://www.facebook.com/BlizzHeroes...40865882789589
Phoenix: Launch a Phoenix to target area, dealing damage to enemies along the way. The Phoenix persists, attacking enemies, and dealing splash damage to those near its primary attack target.
Pyroblast: After a short delay, cast a slow-moving fireball that deals massive damage to an enemy and medium damage to enemies near the target.
I'd guess Pyro will work like Triple Tap in that you could body block with a tank. In fact, both seem fairly similar to Nova's ults.
https://www.facebook.com/BlizzHeroes...40865882789589
Phoenix: Launch a Phoenix to target area, dealing damage to enemies along the way. The Phoenix persists, attacking enemies, and dealing splash damage to those near its primary attack target.
Pyroblast: After a short delay, cast a slow-moving fireball that deals massive damage to an enemy and medium damage to enemies near the target.
I'd guess Pyro will work like Triple Tap in that you could body block with a tank. In fact, both seem fairly similar to Nova's ults.