Something that is rubbish, crap or shitty. Other usages include shizzyswaar for added impact or shiz as an abbrieviated term.
"The shiz" refers to something that is very good. Shiz just used on its own however is used to describe something that is bad.
This lack of crummies is shiz.
Your face is shizzy.
What a shizzyswaar, the ningas are coming to kick my ass!
These crummies are the shiz!