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
If were playing an aggressive manabase, I might see it up into a three-color one, but well have to lean pretty hard into the white
They give you card selection, replace themselves, and naturally fill your graveyard
[Main] Delay You may play 1 level 5 or higher Digimon card with the [Machine] or [Cyborg] trait from your hand with the play cost reduced by 3
Of course, this comfy throw won't only help you during your duels