When an asshole friend in the front seat rolls his window down when the car is approaching a large puddle do that friend in backseat gets hit by a wave of water entering the front window.
The term Hammer slammered is used to describe someone who is beyond Sloshed.
Being the most pissed and feeling like you've been smashed in the face with a hammer.
This state of drunkness normally comes with a case of the sloshed face (Drooped mouth with tounge hanging slightly out), near impossible to stand up let alone walk, and quite possibly passing out. And you will wake up with beer squitz in the the morning.
Person 1: Did you see Jezza last night?
Person 2: Yeh he was hammer slammered, we had to carry him home.
Kin me n' Bezza got Hammer Slammered ont Kestrel Supas last night