This card is great in token decks. Back in the day, my opponents hated when I dropped this. Their 5/5 fliers could now be killed with a Shock. Crypt Rats was a board-wipe for 4. The only real way to deal with this effect was to give your creatures first strike. Nowadays, indestructible gets around this, but back in the good old days this card was to be feared in black or black/red decks. It's one downfall is that it is on the high end of the mana curve with a converted mana cost of 5.
Pros: Makes non-indestructible creatures easily killable Cons: Costs 5 (converted mana cost), doesn't get around indestructible Rating: 3.5/5