An artifact creature card or enchantment creature card returned this way will have base power and toughness 1/1.

If another effect causes one of the returned permanents to become a creature and sets its base power and toughness as it does so, that creature will have that power and toughness; it won't be 1/1. However, a Vehicle returned this way will remain a 1/1 if you crew it, and a Spacecraft returned this way will remain a 1/1 even if enough charge counters are placed on it for it to become a creature.

An Equipment that's also a creature can't be attached to anything. You can activate its equip ability, but it won't become attached.

If a card in a graveyard has {X} in its mana cost, X is 0 for the purpose of determining its mana value.