Rule 107.7

Each activated ability of a planeswalker has a loyalty symbol in its cost. Positive loyalty symbols point upward and feature a plus sign followed by a number. Negative loyalty symbols point downward and feature a minus sign followed by a number or an X. Neutral loyalty symbols don’t point in either direction and feature a 0. [+N] means “Put N loyalty counters on this permanent,” [-N] means “Remove N loyalty counters from this permanent,” and [0] means “Put zero loyalty counters on this permanent.” Loyalty symbols may also appear in abilities that modify loyalty costs.