Many creatures with early enters-the-battlefield effects are actually better as enchantments in this set, so being able to untap and cast Chain Devil, sacrificing Chain Devil to itself, and then sacrificing anything from a Dawnbringer Cleric to a Druid of the Emerald Grove is a game-winning turn
While there are a few cards like this, Gemstone Caverns is the only land that has this trait, and is one of the ways that players can win on the very first turn of the game under admittedly very specific circumstances
Expect to pilot a patient midrange deck that rewards long games and resource accumulation, making it ideal if you enjoy Esper decks that feel resilient and controlling in casual Commander
Cactus Preserve's second ability checks the effects of all mana-producing abilities of lands you control, but it doesn't check their costs or legality
Releasing alongside the set on the same day will be a " 30th Celebration Premium Deck Set Espeon & Umbreon." No further details are known at this time, but the Espeon and Umbreon are implied to feature the new card rarity
The trample is certainly the most important keyword here