Balduvian Horde

Four mana for a 5/5 was muscular for an early-era body, and the design pays for that muscle with a coin-flip you don't get to call. The trigger reads "sacrifice it unless you discard a card at random," and the "at random" is where the bargain bites: the tax is steepest exactly when your hand is full of the cards you most want to keep, and it costs almost nothing once you've already emptied out onto the board. But there's a hard floor under the deal. Because the clause is sacrifice-unless rather than a tax you can haggle down, an empty hand has nothing to pitch and the creature dies on arrival. The ideal moment to cast it is low, not zero. (The trigger uses the stack like any other enter-the-battlefield ability, so an opponent can respond before it resolves; the discard itself, once it goes off, is settled and not negotiable.) This belongs to a school of mid-nineties red that bought above-rate stats with information-and-resource costs instead of mana, downsides that read as fine print until you had to actually live one out. Hand it a chooseable discard and a 5/5 for four becomes too tidy; the randomness is what keeps the body honest, and what makes the card a wager rather than a freebie.