Six mana, and you can bring back all creature cards from your graveyard to the battlefield, and they stick the landing and aren't exiled at the end of the turn, although it is exiled so it's a one-of in Commander and other Highlander formats
is renowned for its extensive and often intricate rarity system
And who doesnt love a free spell that spits out value every turn
Cards like Skrelvs Hive, Mirrex, Reject Imperfection, and Bring the End would all enhance the power of this card as a control finisher and sweeper in competitive play
Deaths Shadow is currently the only deck playing Dress Down in the starting 60, but with so many beneficial interactions in the format, some other decks have already started playing the card in the sideboard as well, and I expect the card to continue seeing play
You can spend the mana you might otherwise spend in casting spells in pumping it up, and it's almost always a 3/3 when you need it to be