Underworld Sailor

Bestow {4}{b}-(If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Underworld Sailor and enchanted creature can't block and have Nyxwalk-(This creature can't be blocked except by creatures with two or more card types.)
Enchanted creature gets +3/+2