How much damage happens if you don't deliver any demonic core essence?

Question

In Azzilon's catacomb we get damage every 20 seconds, on rank 1 after delivering 100 essences we get 4,5% damage based on our total health, but on rank 0 without delivering any essence how much is the % damage?

Answer 1

I decided to test it with a secondary character that hadn't delivered any essence yet, and I took this damage:

19:53:45 You lose 169 mana due to your own attack.

My character has 3386 HP. So, the damage I took is equivalent to 5% of my HP.