Barney
akoum firebird is indeed hasty at 4 mana! I could go either way on the thopter land as I've topdecked it with refuge and 4 mountains, but redundancy says another mountain works too. When they have haste it's usually the 2 damage + x, with x being more damage through combat or nalaar, and board stall as well. Situational, yes. Typing on the phone so I'll be brief, but sometimes it's faster than waiting for vortex, and of course burns just the same to vortex.
One thing I want to point out also is people misplay against the deck often. You play goblins, and they waste turns on board wipes and removal, thinking you're playing rdw wienies. Meanwhile, you're switching gears to burn to the face. GG. You can outrace anything but wienies, from my experience. That's an easy win with twinbolt, arsonist, and perilous myr-der, however.
For anyone unfamiliar with burn strategy, google modern burn primer and check out the starcity article to get started. Infamous Gemini spelled it out already, though.
Combo decks win when you're opponent can't interact with you, which is usually how this deck rolls. I'm not saying tier this or that, but I don't see any decks with enough lifegain to win that don't also lose to the rest of the meta(sic).
Editing to say that regardless of human opponents, this deck will wreck the Ai for quick gold. Just keep mana open to sack things for damage when it plays 3 copies of roil spout or whatever it is.