[2024] Inconsistencies with Blocking Maulers and Crushers' Overhead Attacks: A Bug or Design Oversight?"

I’ve queried this, and this is the information I’ve received:

Certain attacks cannot be blocked (unless with the Ogryn Slab Shield or the Devil’s Claw special parry):

• Scab Mauler Overhead
• Crusher Overhead
• Plague Ogryn Foot Stomp
• Plague Ogryn Slam
• Beast of Nurgle Melee
• Scab Captain 1h Great Slash
• Scab Captain 2h Slam
• Scab Captain 2h Overhead

The Mauler and Crusher Overhead in particular have also a spillover mechanic where they can deal damage to health even at 100% Toughness:

Melee Spillover : Melee attacks with this tag will deal their remaining damage to health if they pierce your toughness without having inflicted their full base damage. Additionally, they will always deal at least 25% of their damage to your health, regardless of current toughness percentage.

Since they deal a huge amount of damage, it’s not unlikely to be one-shotted at full Toughness/Health if there are no damage reduction buffs active.