Rift Bolt is actually better than Spark Elemental if you can't afford Goblin Guide.

But if you don't mind limiting yourself Shard Volley might be better than the both of them.

You might want to try Vexing Devil. Everyone takes the 4 damage because if they don't, you get a 4/3 creature out on turn 1.

Kjartan, actually I would be running Rift Bolts but currently I only have one. My LGS has been out of them for a while now. I'm thinking to replace the Helixes with Rifts though.

ehawkins11, I would love to use Vexing Devil. I was trying to trade three from a friend but he didn't want to part with his favorite card. I don't blame him.

Thanks for the comments. If you guys have any ideas about the sideboard, please let me know. I'm still working on that as well.

Kjartan I missed that you mention this but I am trying to get some Shard Volleys...just my LGS seems to almost always be out of the burn cards I need -_-

I am sure I am just having a duh moment but given nearly every spell you have is less than 3 isn't the Eidolon going to do as much if not more damage to you than your opponent? Seems like it might be better in sideboard. Also a card to consider is Hellspark Elemental. One more than Spark Elemental but has the recursion of Unearth on it to give that extra little kick. Also Sparkspitter would let you turn dead land draws into extra Spark Elementals. If you do end up going the way of adding the suggested cards consider something that gives you an effect when your creatures die so that you get more bang for your buck.

Captain_AHat, thanks for the input! I do agree that at first I thought the same thing about Eidolon of the Great Revel, but actually my opponent would be taking more damage if anything. Since Modern is a fast format (turn 4 wins I believe), most spells cast will be around 3 cmc or less. I do get hit 2 for every spell I cast but so does my opponent. I hit him for 3 at the very least and take 2. My opponent takes essentially 2 every spell they cast -- counters, burns, removal, cantrips, aggro creatures, etc. The only time the Eidolon wouldn't be good is mid to late game against midrange and control, but by that time, my opponent should have 0 life.

I have considered Hellspark Elemental. He's still a consideration mostly for the unearth and trample, but what's keeping me from running him is the fact he isn't a noncreature spell that procs Monastery Swiftspear and that my 2 cmc spots seems kind of settled already except for maybe Lightning Helix. If I were to go the route with effects triggering when creatures die, I would rebuild a completely new deck, going creature aggro focus with cards like Ball Lightning while using Athreos, God of Passage as a recursion/damage toolbox.

Take out Rain of Gore. It's good against a single deck which is not played very often. It is also irrelevant against Leyline of Sanctity which is a huge problem.

I would understand having 1 if there is more than 1 Soul Sisters player in your meta, but having 2 is wasting sideboard slots. Yes, Soul Sisters is a hard matchup, but if you know your opponents deck well, you have a huge advantage.

I'd recommend switching from Mardu into Jeskai, because Treasure Cruise makes the deck infinitely better. The problem RDW used to have was running of out gas, but Cruise eliminates that completely. Black also adds nothing important. Having blue also means you can play Geist of Saint Traft in the sideboard.