Shogun of the Wastes

Let's say your deck has a bunch of 1 and 2 attack creatures, which a lot of aggro decks do almost exclusively. Imagine using a card like Rally that gives +2 attack to all of them - in essence, "double attack" or even "triple attack" - for just 3 power. If your deck is operating correctly, that probably means you just win, and you got to do it for just 3 power instead of 5.

As for Shogun's body, a 6/3 dies to 1-cost and 2-cost removal spells - it's super fragile. It also gets brick-walled by a mere Argenport Soldier. Things get really bad if your opponent has as buffed Rakano Outlaw, or something like that. All of these creatures are reasonable, and of course, it has to contend with anything that costs 5 or less. It also dies to pretty much every Relic Weapon. On top of this, what if you don't have any minions in play? Then the card is even worse. And so if all you really want is the Rally effect, you should really just use Rally.

Of course, if your deck has larger minions - like a mid-range deck, the real "double damage" on Shogun will be better than Rally, but if you're plan is to win on turn 5, why not construct a deck that is more consistent, will have more units, and probably wins even sooner? Shogun is really bad at buffing 1-attack minions - in that case, "double" is just 2 damage, and Rally would have done 50% more. So to use Shogun properly, your minions need an absolute minimum of an average of 3 attack between them, and that's pretty difficult to do in just 4 turns (2 + 2 + 3 + 4 = ~2.75 average, which is less than 3). In reality, you probably need 4 average attack between the first 4 minions to even justify the deck. Cheaper units with Rally is just easier and better.

Hope that helps,

Katie