Joel took over during the middle of the Urza's Saga block and was told by others that he should wait until the next block to make his change, but Joel thought it was important enough that he made the change during the first set he could affectwhich ended up being Urza's Legacy
(It's an artifact with ", , Discard a card, Sacrifice this token: Draw a card.") Creature - Vampire Soldier Removal (CTRL to add secondary) Sac Outlet Laurine, the Diversion Partner with Kamber, the Plunderer (When this creature enters, target player may put Kamber into their hand from their library, then shuffle.) First strike , Sacrifice an artifact or creature: Goad target creature
Eldrazi Mimic This one looked pretty innocuous when it was first spoiled, but it quite quickly became a key part of one of the most notoriously busted decks to ever hit the Modern format
There's tons of examples like this, Vault of the Archangel, Pontiff of Blight, Eight-and-a-half-Tails, Starlit Sanctum
They read, Whenever Zur the Enchanter attacks, you may search your library for an enchantment card with mana value 3 or less, put it onto the battlefield, then shuffle. That means you can find whatever answer you need whenever they attack