Thumper, Iron Man Suit

Bestow {4}{g} (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.)
Thumper, Iron Man Suit attacks each combat if
able.
Enchanted creature gets +2/+2 and has menace.
If enchanted creature would be destroyed, you
may remove all damage from it and destroy
Thumper, Iron Man Suit instead.