Spiritual Incarnation

Outlast {w} ({w}, {t}: Put a +1/+1 counter on this creature. Outlast only as a sorcery).
Whenever you put a +1/+1 counter on Spiritual Incarnation, put a loyalty counter on target planeswalker you control.
All planeswalkers you control with 8 or more loyalty counters on them cannot use their positive abilities.