Doryani invulnerable phase 1 - stone citidal

Fought Doryani in the stone citidal and after getting his hp to under 5% i used lightning warp to cull him.

Then he floated around and continued attacking me.

I used lightning warp and culled him a second time.

He continued to float around attacking me.

I went back to using my normal spells to try and burn him down and the last 1% of his HP would not go away.

Then i died.

in total it was around 10 seconds of him being invincible while still attacking me.