Omaz, Obsidian Blade

Dragon Slayer - Omaz, Obsidian Blade gets +3/+0
as long as an opponent controls a Dragon or there is
a Dragon card in a graveyard.

Whenever a creature dies, choose one that hasn't already been chosen this turn. —
• Draw a card and lose 1 life
• Mill the top card of your library. You may play that card until the end of your next turn.