Hexmark Destroyer

Unearth grants haste to the permanent that's returned to the battlefield. However, neither of the "exile" abilities is granted to that permanent. If that creature loses all its abilities, it will still be exiled at the beginning of the end step, and if it would leave the battlefield, it is still exiled instead.

If you activate a card's unearth ability but that card is removed from your graveyard before the ability resolves, that unearth ability will resolve and do nothing.

Activating a permanent card's unearth ability isn't the same as casting it as a spell. The unearth ability is put on the stack, but the card is not. Spells and abilities that interact with activated abilities (such as Stifle) will interact with unearth, but spells and abilities that interact with spells (such as Cancel) will not.