The Lorwyn expansion introduced the commands cycle. There were five of them. There was one for each color. This review will discuss the white one. The white one is called Austere Command.
Whille at first glance, the cost may look expensive at six mana, it is actually reasonable once you read the text. The card can do a combination of two of these four abilities.:
destroy all artifacts
destroy all enchantments
destroy all creatures with mana cost 3 and below
destroy all creatures with mana cost 4 and above
This particular card is really destructive against artifact or enchantment based decks as it could wipe out their setup in one fell swoop. Not only that, a two effect for one card gives you tremendous card advantage. The best part about this card is the undervalued $2.50 price tag. I personally used this card in casual play and it is awesome in blue white control decks. It is extremely undervalued in my opinion. a card like this should be twice its current worth at the very least.