u/Le_Vagabond

invulnerability phases. that's what hatred is.

• Lilith: goes invulnerable several times in all phases of the fight
• Mephisto: goes invulnerable every 15 seconds in all of his forms
• Harbinger of Hatred: goes invulnerable for an entire phase of his fight
• Lord of Hatred expansion: added the new, fun, amazing affix "invulnerable until you kill this other elite that's tethered to me"

and obviously in all of those cases the fact that they're invulnerable DOES NOT STOP incoming damage to you.

so yeah I'm pretty sure that's what Hatred actually is.