Ertai Resurrected Four mana is a lot of mana to keep up at any given time, and giving opponents extra cards isnt something you want to be doing, group hug decks excepted
Depending on your budget, size of your collection, and value of your cards, you can start with a convenient option like a D-Ring binder, and work your way up from there
Type - Creature, Enchantment, Instant, Sorcery, (colored) Artifact, Planeswalker 4
Regarding Shadowless Cards Shadowless cards are from the first two print runs of Pokemons base set and are noticeable if you examine the bottom of the Pokemon's frame, where drop shadows are not visible, but appear in later printings
While green decks hardly lack options for +1/+1 counter production, you really need counter doublers to outspeed your opponents and build up a terrifying board
That's massive potential card advantage in Commander