Excava, the Risen Past

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.

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

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

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.