Assuming that Modern Horizons 2 doesn't have any surprise supply issues, it's pretty safe to say that the value of the cards found in draft boosters (so, normal printings, primarily) will lose at least half of their value, on average, over the next couple of months
Here is my version for inspiration, your comments are welcome
The commander is tracked across zone changes for this purpose (for example, if one player takes control of another player's commander, any damage that commander already dealt is still counted)
Those experience counters then turn into +1/+0 for your creatures
That's nasty good in all of the places, like in tokens matter with Green dorks, aggro to refill your hand, or landfall making dorks like Insect tokens from Scute Swarm to draw a ton cards in decks with just Green or other colors like Simic Landfall or Selesnya Tokens