Leviathan, Sin of Envy

Trample
Leviathan cannot attack or block unless an opponent has more lands than you control.
As long as an opponent is the Monarch, Leviathan has Double Strike.
As long as an opponent has the Citys Blessing, Leviathan has Annihilator 2.
As long as an opponent has an emblem, Leviathan has Indestructible.