The thing is about SoI, it's not very useful in a non Shard deck, and the only efficient way to utilize it is to build something like the ultimate, what newbiecake did. Like any other decks, the ultimate also has its weaknesses. It focuses on getting out a first/second turn powerful golem out, but after that, you're defenseless. You have a rampaging monster on the field, but your equipment, hands, and control are all nonexistant. A single RT, antimatter, dusk, dim, fog, or BB or even wings will result in a loss for you (although SoFr+SoW). After your first golem, all your shards are gone as well, so it's very unlikely you'll be able to put down another such golem.