Nelkrez, Host of Delgar Woods

Reach (This creature can block creatures with flying.)
Wither (This deals damage to creatures in the form
of -1/-1 counters.)
Whenever Nelkrez blocks or becomes blocked by
a creature, choose one —
• Put a -1/-1 counter on target creature.
• Put the top card of target player's library into
his or her graveyard.
• Target player loses 1 life.