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The enigma cards mention a Combiner keeps an upgrade in each slot, but here's a weird scenario involving that: Say Prowl, Strategic Mastermind is upgraded with a Power Sword. Since he's a melee character, he can obviously take this upgrade. But could you keep that Power Sword on Optimus Maximus when he combines, even though he's a ranged character?

Yes.
Source: Wizards of the Coast (2019-02-01)    【Link to Ruling】
Tags: Combiner