By letting you cast spells as though they had flash from the very first turn, Leyline of Anticipation transforms your opponents' turns into your own private main phase. Once you have Glen Elendra Pranksters waiting in the wings, dropping free artifact creatures like Memnite and Kobolds of Kher Keep becomes an engine of perpetual motion; each zero-mana creature hits the battlefield to trigger the Pranksters, which bounces the other zero-drop right back to your hand to be cast all over again. Because these cards demand no mana to replay, you can loop them indefinitely to flood the board, trigger endless enter-and-leave-the-battlefield effects, and build an astronomical storm count right out from under your opponents.