This seems like an interesting use for paying attention to word counts. If you can get a 2-for-1 or greater more often than not, then this is a consideration in larger cubes I would think. Modal cards with the possibility of card advantage are very often strong considerations for cube, barring a cost that is reasonably appropriate to the effect.
Not being able to control how strong this is in terms of what you get from your opponent makes it a bit too unpredictable for me. Sometimes it will be sick, other times you're leaving stuff behind you can't afford to for 3WW even if what you're getting rid of is good, or getting rid of the best thing puts you back to a worse spot if it nails some of your own stuff. Austere Command seems like a similar version of this that's easier to control.
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