Back up, wait to parry, then stagger again because it has a cooldown. The Pulverizer heavy attack staggers the Scrake. This takes very good timing and I recommend body armor when you try it. In the higher difficulties, a Scrake can take you down from 100% health to dead in 1-2 hits if you're not wearing armor.
Where before it was possible to Fire Axe stun him or make an easy headshot with the crossbow in KF, Early Access players don't have nearly the same kind of firepower. Seriously dangerous once he closes in, so don't let him corner you. You'll know when this one is inbound by the sound.
