Id been meaning to add Powerstone Shards to my Cube, and I bought some newer cards for my Commander deck
He encourages you to build your deck with a lot of mana value 3 or less creatures, and gives you a mini-Winota style effect
Alpine Moon Blood Sun Bombardment (playtest) Dress Down Final Showdown Glorious End Humility Kitesail Larcenist Overwhelming Splendor Poppet Factory Power Sink Sludge Monster Sudden Spoiling Titania's Song Toxicrene Vedalken Humiliator Vraska, Betrayal's Sting Will Kenrith Wrath of Sod (playtest) Yixlid Jailer You Exist Only to Amuse Zhao, the Moon Slayer
Tornadus, Thundurus & Landorus [Jumbo] #66 (Pokemon Promo | Pokemon Cards) prices are based on the historic sales
Another example of this is the maindeck Spellskite we see in many Infect and some Twin lists, a card that runs double-duty protecting their win conditions and staving off Burn
This gives Mew ex an advantage over them since it doesnt dump energy after attacking