Sacrifice as an activation cost is a way to increase a spells cost without having it cost additional mana
There are lots of ways to sacrifice permanents in the Blood Rites deck, which can potentially turn Carmen into a terrifying monster
Effects like this one can turn an EDH game around
Crystalline Giant /**Mechagodzilla, the Weapon** This was cut when whittling the deck down to 99 cards, but not because of the obvious issues playing with it in paper magic
Unless youre desperate and are willing to basically give your collection away for a fast buck, stick with the other guys I talked about above (eBay, TCGPlayer, etc.) RUNNER UP: Star City Games is definitely another place you should consider for selling your Magic cards
They are both good at creating a lot of early weak creatures, which can be used effectively to pay for a convoke card