In a deck with cheaper interaction and other spells, well, not so much
Just think of Grunn, the Lonely King attacking alone with Rafiq on the battlefield: Grunn doubles its power and toughness, gets any exalted triggers, and then gains double strike to smash in for over twenty points of damage
I'd put Etali, Primal Conqueror above the others because its a better card overall
The creature that enters the battlefield doesn't need to have lesser power than Shadowfax (this can happen if it enters with +1/+1 counters on it, for example)
While I personally find it fun to run pet cards and lesser played gems, its safe to say that there are a good number of strong Magic cards I wouldnt want to leave home without
-4 You get an emblem with "Your opponents play with their hands revealed" and "Whenever an opponent draws a card, this emblem deals 1 damage to them." Loyalty : 4 Legality Vintage Legacy Premodern Modern Pioneer Standard Duel Commander Commander Multi Historic Alchemy Illus