I really don't like the "5 or more cards" restriction. Would this be too good if you could always do the discard on ETB? I don't think so.

The set has a Wisdom vs. Hellbent theme... it's hard to explain why these sort of cards are fun until you draft the set. It gives players something to work for when drafting (since many cards are Wisdom or Hellbent enablers), and acts as a minigame when playing. Cards that do both at the same time are extra usefull (this card is a Wisdom card that Hellbent enables). It's also worth noting that this is an expansion of the core block which had a healthy number of "5 cards or more" cards, so this would be a play on that.

That being said, I understand the poopy face being made when looking at this card. I tried to give this and the blue one (the two colors stuck between Wisdom and Hellbent) simple abilities for their colors. But, maybe Rampant Growth isn't simple enough. From the point of view of "I want my players to jump through these hoops" it works splendidly, but from a player point of view, it's stinko. I'm going to have to think on this one.

I see. Yes, I think your assessment is fair, then.