A protean term that is used to convey an evaluative judgment of a thing or a state of affairs. Something that is "cooked" may be very good, very bad, or somewhere in between. The adjective may readily carry further nuances, depending on the context.
The word otherwise does not lend itself to exhaustive definition in the abstract. Its meaning in any particular situation – or whether it has a precise meaning at all – depends heavily on the speaker's subjective purpose. Ascertainment of that meaning requires considering the use of the word in its broader conversational context.
An altered state of being, whether it be chemically enhanced or a result of sleep deprivation and/or sensory overload. Usually occurs in the midst of and/or aftermath of a rowdy social engagement or bender (e.g. a music festival spanning one or more days, consecutive nights of exposure to alcohol and drugs in combination with loud music of an assorted variety, &c.)
Dude: Have you heard from Scott since he's been in Vegas?
Girl: Yeah, he sent me a clip from a pool party he went to where Eric Prydz was playing. He won a stack of money playing roulette and spent most of it on coke.