Njad'nu, the Never King

Dominion: If Njad'nu, the Never King is in the
command zone, battlefield, or graveyard, all skeletons have Unearth {u}{b}{r}.
When Njad'nu, the Never King enters the battlefield, put a +1/+1 counter on all other skeletons, then place the top four cards of your library into the graveyard.
Whenever Njad'nu, the Never King attacks or
another skeleton enters the battlefield, all
skeletons receive +1/+0 until end of turn.