4/5. In standard, mono-green has exactly two permanents that can regenerate a creature: Experiment One and this. Unless you're playing Green-Black, those are your choices. This is a KEY card to any standard deck that is two-colored, green and some non-black color, IF it is creature-based AND it wants to keep its creatures around after Supreme Verdict. It's hard to imagine not having 1 or 2 of these in your 75 if you have such a deck. At it's best: against aggro, you have an impossible-to-deal with blocker; against control, you have an impossible-to-deal with attacker. On a Witchstalker or Gladecover Scout, this thing is incredibly effective at keeping a body on the battlefield.