The Liber Bubonicus

When The Liber Bubonicus enters the field, target friendly Planeswalker gains +4.
The Liber Bubonicus enters the battlefield tapped.
{t}: Deal 3 damage to the enemy opponent.
{b}{b}{b}, {ut}
This decrepit tome bristles with dark secrets and eldritch powers. Reading from it summons dark thoughts and grim deeds.