We might disregard the card because it looks like a one-for-one, but then we realize its not, since it replaces itself
If the chosen permanent is copying something else (for example, if the chosen permanent is a Clone), then your Malleable Impostor enters the battlefield as whatever the chosen permanent copied, with the stated exceptions
Bundles also come with promos, featuring one of the legendary characters who took sides in the Brothers' War, Queen Kayla bin-Kroog
In this set, the term 'Legendary Creature' (or just 'Legend' in older sets) haven't actually been invented, which creates a bit of an anomaly where Aladdin and Ali Baba are meant to represent actual characters instead of a type of creature like a Sengir Vampire or a Grey Ogre
You can mitigate its effectiveness by not trading off Hero tokens versus black decks or relying on something like Hecteyes
But once you start combining multiplicative mana effects and mana sinks like activated abilities or Buyback spells, anybody who isnt already comboing off will struggle to keep up