Assassin Class Starter Pack contains three predetermined Assassin cards unique to this product
It can make a small army of flyers to evade Moat (or block opposing flyers), and it if sticks around until your next upkeep essentially renders an opposing Swords to Plowshares or Disenchant irrelevant, as it will have had time to separate in to four smaller threats at the beginning of your upkeep
The first one did a lot for ninjas, while the second went nuts over squirrels
If you control your commander, you can cast it for free and instantly give all your creatures indestructible
Urborg, Tomb of Yawgmoth has some very powerful synergies with fetchlands
There's Ultima, which sweeps up the board, and Squall, SeeD Mercenary, who sweeps you off your feet