its gone tits up

1. something that has failed spectacularly, in a way that could not be predicted (it went tits up) can also be used in this case)
2. something that has broken slightly

Friend 1 - thought you were going out tonight
friend 2 - its gone tits up went tits up, friend 3 was sick and friend 4 had car issues
friend 1 - that went properly tits up then

gone off hamster food

When you leave hamster food out too long and it goes all moldy and stale like cardboard.

The gone off hamster food tastes like cardboard.

Gone for milk

Usually associated with your father, as it is his favourite catchphrase

Your dad: I'm going for milk
You:ok
He never came back
This is an instance of gone for milk

gone off lime

When you leave a lime out too long and it goes moldy.

The gone off lime tastes like citrus shit.

ching chong your existence is gone

A meme were a Vietnamese tree soldier hunts Americans in Vietnam down and turns them into flesh pancakes.

American: a good day to take down some Vietnamese soldiers
Vietnamese tree soldier: ching chong your existence is gone
American: fuck this shit I'm out
Vietnamese tree soldier: *turns American into flesh pancake*
Vietnamese tree soldier: looks like my work here is done

ching chong your existence is gone

a Vietnam war meme were an American gets turned into flesh pancake when Vietnamese tree soldier shoots him

American: Ah what a normal day destroying some Vietnamese soldiers.
Vietnamese tree soldier: ching chong your existence is gone
American: fuck this shit I'm out
Vietnamese tree soldier: *turns American into flesh pancake before he could frun*
Vietnamese tree soldier: looks like my work here is done

gone off cheese

When cheese is in the fridge too long and it goes moldy.

The gone off cheese smells like farts.