Ugin's Construct

A 4/5 for four colorless mana is an undercosted body, and the design pays for it with a tax that lands hardest on exactly the decks that don't want it. In a heavy artifact or colorless shell, the entry trigger asks for a colored permanent to feed it, and a pure colorless deck may have nothing to give, so the trigger simply resolves and does nothing. The constraint rewards commitment to the plan: this is a beater that gets better the more committed you are to the colorless plan it belongs to, and worse in a deck splashing colors it may not want to lose. That tension is the whole point of the slot, a colorless creature that rewards mono-color discipline and punishes the kind of mixed board most aggressive decks already field. It sits in the small family of cheap fatties that demand a sacrifice on entry, where the question is never the rate but what you have lying around to pay it with, and Ugin's name on the card frames the cost as deliberate: a colorless power testing whether you can afford to keep one of your colored things.