Dauthi Voidwalker

If a card has {X} in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.

If you cast a card this way, you may not cast it for any other alternative costs it has, but you may pay for additional costs, such as kicker costs. If the spell requires an additional cost, you must pay that cost.

If an attacking creature has multiple evasion abilities, such as shadow and flying, a creature can block it only if that creature satisfies all of the appropriate evasion abilities.