Not even just the holos, but commons and uncommons like Eevee, Exeggutor, Butterfree, Rhydon, Weepinbell, etc
Special sets, like Pokemon Celebrations, feature reprints of desirable cards from the past
Stretch your money with base-art versions, Japanese cards, and lightly played condition
Earthcraft is the best source of mana to fuel a number of infinite combos involving Doubling Season, Cathars Crusade, The Meathook Massacre, and Corpse Knight, among others, but these cards only scratch the surface of your combo potential with this commander, so if thats your preferred style of play, the linked primer above is going to be your best starting point for deck construction
Esper Panorama) and in most decks are just better versions of Evolving Wilds and Terramorphic Expanse