mtg cards like overwhelming stampede where X is the greatest power among creatures you control Overrun Effects : r/mtg

However, this card is also 3BB: Heros Downfall (a card I really expected to be in the set)

Appearing in Magic Foundations , the Dragon doubles any damage from any source you control that would deal damage to an opponent or a permanent an opponent controls, meaning the output from Twinflame Tyrant can become ridiculous rather quickly

Tifa, Martial Artist seems to be one of the strongest commanders from the precons

Its ability to circumvent commander tax at instant speed makes it incredibly difficult to hit with lasting removal over the course of a game, and the fact that it can pop in at instant speed to untap your best permanent or tap its biggest threat has screwed up more than a few carefully orchestrated plans

I hope this helps inform your buying decisions