The Pokmon Company designed this game for parents and children aged 6 and older
Even if these effects are justifiable in other colors, its a complex question, and one I believe misses one of the biggest points: green is powerful because of redundancy
These cards can include any type of Trainer card, such as a Pokmon Tool
It has a kind of reasonable floor as most decks can take advantage of the reanimation, but it is probably not going to be very good in your typical White deck, and like a B in a GW deck that is good at gaining life A 3-mana 0/4 that ventures into the dungeon is probably already a decent card for the format, but this looks to be one of the bigger payoffs for completing dungeons at lower rarities, as it becoming a Flyer is a pretty big deal -- that kind of size almost always matters on an evasive creature, and it is going to give you value when it ETBs no matter what
For a deck with Sazh's Chocobo, Mightform Harmonizer, and Earthbender Ascension, the interaction with Erode turns the card into a tactical Giant Growth (or more), especially when you are attacking with multiple Landfall Creatures
Was this the first Secret Lair