It seems like every set adds to this in some way, even if its only with an exclusive rarity, but Japanese Showcase cards are a rarity that anyone can get, provided they pick up the right packs
Bonus: Where To Sell Bulk Do you have so much MTG bulk that you can literally fill a swimming pool
Oran-Rief is a little narrower but costs significantly less mana, and youve got a decent number of green creatures
The other mentions are basically any of the Gisa or Geralf iterations, all of which are easy includes in any deck that cares about having the best Zombies in Commander in it, because they make a lot of Zombies and have some excellent synergies
Nalathni Dragon Nature's Blessing Shield Bearer Kjeldoran Skycaptain Icatian Phalanx Errand of Duty Mesa Pegasus Knights of Thorn Benalish Hero Greater Morphling Volunteer Reserves Benalish Infantry Urza's Avenger Helm of Chatzuk Battering Ram Pikemen Teremko Griffin Noble Elephant Urza's Engine Kjeldoran Escort Soraya the Falconer Beast Walkers Ayesha Tanaka War Elephant Wall of Shields Baton of Morale Dire Wolves Kjeldoran Warrior Kjeldoran Skyknight Kjeldoran Phalanx Kjeldoran Knight Formation Cooperation Mishra's War Machine Timber Wolves Fortified Area Icatian Skirmishers Icatian Infantry Wall of Caltrops Tolaria Camel Best Banding Cards #5
The green boon, Giant Growth, was considered an iconic card of Green and had appeared in every core set until the printing of Magic 2012