How much physical damage does T13 Core Malachai's Slam deal?

Kind of surprised, I just got oneshot 2 times in a row by this boss without any map mods through 6.2k life, fortify and 50k armour. (and 83/68 block)

According to PoB in order to oneshot me that would require a physical hit of 10.000.

When I look at POEDB the skill is called "MalachaiTeleportSlam", not "IncaBossExplosion" which is the one Vaal Oversoul is using and split between phys and fire.

Is that dude actually dealing 10k physical? It just can't be a crit 2 times in a row and with that much attack block I'm convinced it counts as a spell.

http://poedb.tw/us/item.php?n=Core+Map

This is the only thing I found that comes close to answering.