Both vintage and modern Pokemon cards follow this system, so the age of your cards wont play a role here
The first commander of the second deck, which features the three colours green, white and blue, is Galea, Kindler of Hope
But the real treasure is its ETB ability that lets you swipe an instant or sorcery from an opponents graveyard, exile it, and cast it that turn using any mana, making it beneficial for attrition or grindy matches
Outside-the-box cards: Reap, Gravestorm Phenax, God of Deception Phenax kind of builds itself, but instead of a raw mill deck, Id rather go with something that mills things so that you can use them
Only, instead of placing Timmerian Fiends into your graveyard, you place it into your opponent's graveyard
After all, something this massive deserves a herald