Thats a very useful way of weakening every character if youre playing head-to-head with a single opponent who has a field full of cards, but becomes even more powerful in multiplayer matches - where its ability will affect every character (except yours) currently in play
I expect this to happen, but I would want that each main villain and lead protagonist get a rare or mythic slot
Lands often have no use late game in limited, so sacrificing a couple to give yourself a few extra cards never hurt, especially when the additional costs involved "tap" and not "spend mana"
While this cards pack tactics ability is certainly nifty (gifting you a free 1/1 Gob if your attacking creatures powers are equal to six or more), its this cards one red and one colorless activated ability that truly shines: being able to give haste and a healthy boost to all of your Goblins powers can sometimes end a game (for one player, at least) on the spot
Harmonic Prodigy helps to get your battlefield set up much quicker than normal , allowing you to get a head start on all your opponents
