Mystery Booster 2

Artifact Creature — Elemental Champion

Instead of taking turns as normal, players take their phases sequentially. (For example, you take your beginning phase as the active player, then the next player in turn order becomes the active player and takes their beginning phase. After each player had a beginning phase, do the same for first main, combat phase, second main, ending phase, and then beginning phase again. If this creature leaves the battlefield, the active player continues their turn as normal.)

Runed Terror

Emrakul, the Promised End

Legendary Land

{T}: Add {C}.
{1}, {T}: Exile the bottom card of target opponent's library.
Whenever one or more cards an opponent owns are put into exile, put a release counter on The Heron Moon. Then if it has thirteen or more release counters on it, sacrifice it and create a copy of Emrakul, the Promised End. Cast it without paying its mana cost.

The Heron Moon

Land

Slumbering Waterways enters the battlefield tapped.
{T}: Add {G} or {U}.
Flying, vigilance, trample

Slumbering Waterways

Level up {1} ({1}: Put a level counter on this. Level up only as a sorcery.)
{T}: Add {C}.
LEVEL 1-7
{T}: Add {W}, {B}, {G}, or {C}.
LEVEL 8+
{T}: Add {W}, {B}, {G}, or {C}. Scry 1.