Seaking eldrazi

Islandwalk hexproof annihilator 2
Deviod Echo {5}{u}{u}{u}{c}{c}
{t}{u}{u}{c}{c} sacrifice 2 Lands
Mill half your library survil 3
Then if you have 20 or less cards
In your library take an extra turn
Other Eldrazis you control can't
be blocked and get 2/-2 As long as you have
50 or more cards in your library