I'll slice you open like an envelope

Used commonly by football hooligans, 'I'll slice you open like an envelope' can hint that the person saying the phrase is carrying a knife and intends to use it lethally on the person they are saying the phrase too. Can also mean that the person it's being said too acts 'big' and 'untouchable' and the person saying it is easily going to beat them up.

'Threat'

Football hooligan- 'you think you can take me on?'
Opposing team football hooligan- 'I'll slice you open like an envelope'

Schlonghead

Schlong = penis. An alternative way of saying dickhead.

Why's my phone not charging? Coz the plugs not on you schlonghead