Sacrifice [Beta Edition] Media Promos Set: EX: Sandstorm Type: Lightning

Set: EX: Sandstorm Type: Lightning Rarity: Ultra Rare Retreat cost: Colorless

Set: Commander 2014 Type: Artifact Rarity: Rare Cost: {2} Black spells you cast cost {1} less to cast

Set: Platinum: Supreme Victors Type: Colorless Rarity: Holo Rare Retreat cost: Colorless

you can Normal Summon it to have it treated as an Effect Monster with this effect:

determining which should be studied

Sacrifice [Beta Edition] Media Promos Set: EX: Sandstorm Type: LightningSet: Beta Edition Type: Instant Rarity: Uncommon Cost: {B} As an additional cost to cast this spell, sacrifice a creature. Add an amount of {B} equal to the sacrificed creature's mana value.