You may choose not to untap Helm of Possession during your untap step.
2, Tap, Sacrifice a creature: Gain control of target creature for as long as you control Helm of Possession and Helm of Possession remains tapped.
Near Mint Condition
A card in Near Mint condition shows minimal to no wear from shuffling or general play. Cards classified as Near Mint/Mint are generally indistinguishable from cards in an unsleeved deck of other Near Mint/Mint cards. Foils in this condition have little or no scuffing or clouding on the front and edges of the card.