That means Mulldrifter draws you two cards when you first cast it, then another two cards at the end of your turn, and another two cards at the end of every future turn
The 100 brings Princess Luna with her Nightmare Moon transform, Princess Celestia leading Horse tribal, King Sombra, Queen Chrysalis, Lord Tirek, Discord, Starlight Glimmer, Trixie, Sunset Shimmer, Big McIntosh, Maud Pie, Cheerilee, Daring Do, and the full Equestria cast
You'll get to relive events from the early days of Magic that took place on its original plane of existence
002-149 and 003-142 represent our first playable characters in a lot of matches, so could be kept
As for Shadow itself, card draw is nice but the real draw here is the fact you can repeatedly drain each opponent of life whenever you trigger this ability