AS aggro as aggro gets. Every creature swings for at least 2, and the curve caps at 4. And unlike most aggro decks the synergy allows this deck to scale well into late game because it has so many win conditions.
1-drops: You want to come out of the gate swinging and having a curve heavy with 1-drops allows you to do just that. Bloodsoaked Champion is fantastic because his raid trigger is easy to get off and he will remain a threat throughout the game. Mardu Woe-Reaper is another great addition because not only does he swing for 2, but he disrupts opponents, gives you life constantly, and destroys reanimate decks (Sultai Whip anyone?), he also triggers a certain ferocious 2 drop we run. Finally Mardu Shadowspear, although a 1-drop, is a mid game threat. I wouldn't open with him so I only run 2 because ideally you want to use his dash ability in combination with a nice board setup, if you have even 1 Chief of the Edge out he will be a cheap and abusable 3 damage your opponent won't expect.
2-drops: The meat and potatoes of the deck. Your chiefs buff your warriors to astronomical levels. Just have 2 chief of the Scales out means a board of 4-5 power warriors that can potentially end the game in one full swing. Just 2 chief of the Edges out means a bunch a board of bulky warriors who can out trade any morph or manifest creatures out. But while you want to sit on your chiefs, you want to swing full on with Sightless Brawler and Battle Brawler. By turn 2 you can essentially have a 3/2 with first strike and by turn 3 he can be a 4/2 with first strike, it really is insane and he only gets stronger as the game goes on. Sightless Brawler is good too, but what really makes him shine is his bestow which makes for a nice late game trick that can break a stalemate and end the game in your favor.
3-drops: Mardu Strike Leader amplifies this board pressure by spawning tokens that benefit from the buffs of your chiefs, so if you have one of each chief on the field your strike leader is pumping out 3/2 tokens each turn!
4-drop: The final win condition. If you are playing aggro, 9 times out of 10 you won't even get to this point, but if you do and the games drags then the final boss appears. Brutal Hordechief essentially ends the game within 2 turns of his summon. By the time he's out your opponent should be lower than 8 life and in many cases just declaring an attack will win you the game. Even if your opponent has a board of tokens (Elspeth) attacking with 4-5 creatures creates a 8-10 life swing he or she can do NOTHING about. 8-10 life swing, IN LATE GAME, just by declaring an attack. And if they are STILL somehow alive, his ability ensures that you will swing for as much as you want by having all enemy creatures block a token or something GG.
Removal: Both are strogn late game removal that removed NON-LAND PERMANENTS, meaning they are versatile. You have 5 means of taking out any creature, artifact, enchantment, equip, god, planes walker ANYTHING.
Sorin: He's more of a "might as well" addition. if you can't afford him then don't add him he doesn't add THAT much. His first ability is really good in aggro decks like this, but other than that he does little to supplement the strategy. He is a complete win moar card.
