Ori

{1}{u}: Ori becomes a Spirit Elemental with base power and toughness 2/2 and flying.
{2}{r}: If Ori is an Elemental, it becomes a Spirit Elemental Guardian with base power and toughness 3/3, flying and menace.
{3}{g}: If Ori is a Guardian, it becomes a Spirit Elemental Guardian Avatar with base power and toughness 5/5, flying, menace and shroud.