Kolaghan approves of attacking, and attacking is what this deck does. It's still a midrange deck, as you can see by the
Outpost Sieges and five-drops, but it does a good job of getting value while still pressuring the opponent.
Dragon Fodder is the
Raise the Alarm that red decks have been looking for. It may be strictly worse, but it's the right color, and for decks like this, that's all that matters. This deck is capable of making lots of tokens, clearing out blockers, and—if a swarm fails—exploiting the tokens with Sidisi.
Using Sidisi to turn a Goblin into a Dragon is awesome, and she can also nab anything, from removal to
Outpost Siege, depending on how the game is going. If Sidisi wasn't legendary, I could see running more, but as is I like the 4/2 Stormbreath/Sidisi split.
The pair of Dragons is what gives this deck much of its reach. Between Stormbreath and Kolaghan, the opponent is always in danger of eating a chunk of haste damage, and both Dragons have abilities that can potentially deal a ton of extra damage on top of that.
By playing the two removal colors, this deck also gets to kill everything while getting value.
Murderous Cut is incredibly efficient,
Draconic Roar deals a ton of damage, and
Stoke the Flames is still one of the best cards in Standard when combined with tokens.
Kolaghan attacks early and attacks often, while still retaining the ability to take the game long.
Outpost Siege and
Ire Shaman give the deck additional card advantage, and Sidisi is one of the best topdecks if you have a token lying around.