The Crystal Shard

At the beginning of your upkeep put X
Sun Counters on The Crystal Shard where X
is twice your devotion to white.
{t}: Create 2 X/X Wall Tower Creature
tokens with Deffender, Deathrouch, Indestructible and "This Creature may block
any number of Creatures" where X is equal
to the number of sun counters on The Crystal Shard.