Charlie Sheen fired a warning at his ex, Brooke Mueller, when he heard about her trip to a pawn shop and possible drug relapse -- "Don't pick a fight with a warlock ... 'cause you're gonna lose."
Charlie got wind of Brooke's strange pawn shop visit ... last night in Toronto -- and told Canadian entertainment show, etalk ... there are consequences if Brooke falls off the wagon.
As we reported, Brooke has to get a new drug test by 6PM tonight.
Clock is ticking ...
Charlie to Brooke: Don't Fight a Warlock ... You'll Lose
4/15/2011 9:30 PM PDT BY TMZ STAFF
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