Beatdown is a box set that was released in October 2000.
The name was derived from a slang word that was used at the time for aggro decks. Players often said they were "applying a beatdown" when creatures were attacking and dealing lots of damage to an opponent. A "Beatdown deck" is essentially a “weenie” deck full of creatures that cost between one and four mana.
Beatdown is notable for containing the only black-bordered card ever printed with the {Y} symbol, a reprint of Fireball. All other printings of the card, as well as its Oracle text, use only {X}. The {Y} symbol has otherwise only been used on the Unglued card, The Ultimate Nightmare of Wizards of the Coast® Customer Service.