You are, but its an easy pitfall to get into.
Its a 4 drop. In the crazy aggro that is Tempered Steel, a 4 drop had better be a finisher and not just a control effect.
The Mox opals are what makes the deck. Its essentially a land in the deck, and it turns Tempered Steel from turn three into turn two. An ideal starting run is Land, Opal, a couple of 0 costers and Overseer. Turn two is tempered, and swing with 2-3 4/4s. Repeat next turn, either buffing again or swinging in with the overseer, who is now 4/4 as well.
Its an aggro deck, not control, don't play it like one.
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