After all, who heard of a wall dropping dead of fright
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
And that's certainly worth paying 4 colorless mana for
[2] Cascade is a powerful ability, especially in conjunction with the suspend cards, (like Living End) since cascade only cares about the CMC
Cards like Metalworker, the Signets, and the Moxes can be used to provide massive amounts of value
And it helps that Hasbro owns both, so theres no sticky legal hoops to jump through to borrow licensing for one or the other