Questing Beast
Legendary Creature — Beast
Vigilance, deathtouch, haste
Questing Beast can't be blocked by creatures with power 2 or less.
Combat damage that would be dealt by creatures you control can't be prevented.
Whenever Questing Beast deals combat damage to an opponent, it deals that much damage to target planeswalker that player controls.
Illustrated by
Throne of Eldraine Promos#171pMythicEnglishLegality
Rulings
Once a creature with power 3 or greater has blocked this creature, changing the power of the blocking creature won’t cause this creature to become unblocked.
Questing Beast only stops combat damage from being prevented by effects that specifically use the word “prevent.”
The damage Questing Beast deals to the target planeswalker as its last ability resolves isn’t combat damage.
If the opponent dealt damage controls no planeswalkers, Questing Beast’s last ability simply does nothing.