Couple of suggestions for your sideboard:

Dismember for any deck running goyfCombust for those control decks with colonnademaybe even Vexing Shusher to help against any control heavy matchup.

Also, is 18 lands enough? Ive usually seen burn decks running 19 or 20, but if it works, don't let me tell you otherwise.

Finally, Grim Lavamancer would be good, even in this fetch less version, to help get extra value off your spells.

Looks like a fairly standard modern Burn deck though, so +1 for doing 20 to the face :)

If you are using Shard Volley and Searing Blaze you will want 20 lands, because otherwise those cards will just create a hindrance to you. Especially without fetches on the Searing Blaze

Skullcrack is generally to be kept at 2 or 3 because it can't target creatures.

Eidolon of the Great Revel should be kept in the side because there are too many times where provides no net damage, and he generally just turns into a 2 mana for 2 damage that also hurts you for two. He is excellent against the mirror, affinity, zoo, and storm but beyond that he hinders you more often than not. You also have to remember that Jund decks, Bxx knights, AEther Vial aggro and pod can all cheat their creatures into play, making Eidolon of the Great Revel a lot weaker than normal.

Magma Jet is a pretty good card as it can help set up your next two turns, really important if those next two cards happen to be pointless lands.

Vexing Devil should be removed, choice cards are not good in modern as it is whatever you don't want him to be. Sure it might be good turn one, but on any other turn Vexing Devil will really lack in terms of damage.

I would suggest against Hellspark Elemental on the condition that you are using Grim Lavamancer . While alone the hellspark is a good card, one card for 6 damage is pretty nice, but the exile makes Grim Lavamancer 's ability less worth while.

A few good game ending cards are really useful. Ball Lightning I generally have as a 3 of (a good replacement for Hellspark Elemental ) and then Elemental Appeal I keep as a two of.

Hope this helps.

Also:

Mono red, because AIN'T NOBODY GOT TIME FO' THEM BLUE MOON DECKS!

Blue moon?

A deck type using Blood Moon . Blue comes from the choice of colour.

Oh okay. I'm new to modern so I don't know all the deck archetypes yet lol

It's a very fringe deck archetype. Hardly ever gets used. I only learned of it a few months ago.

Perhaps run Ball Lightning . At it's best, it's a 3 drop to hit for 6 and a good thing to curve out on. At it's worst, it's a target for your opponent to waste a counter on.

Ball Lightning is pretty slow in mono red. There are better things than it.

http://www.mtgsalvation.com/forums/the-game/modern/established-modern/219892-burn

This is a good thread to look at. Lots of good ideas here.

Wrong ness64. Very wrong. It very powerful as a finisher along with Elemental Appeal , and both are vastly important when Leyline of Sanctity is a thing.

Femme_Fatale In my experience, Ball Lightning didn't work for my deck. But you might be right.

I feel like 1x Thundermaw Hellkite or even a Stormbreath Dragon deserves a spot in here, just to have a hasty finisher that can hit the field and end the game right then and there.

also, a couple Teetering Peaks and maybe some kind of man land would help for sure

Thundermaw and Stormbreath are both five mana, which I think is too much for this deck. If it's turn five and you're not dead yet, I'm doing something wrong.

Looks pretty sweet. If you took out some Ball Lightning -type stuff, you could probably add more spells and get some Monastery Swiftspear , Not sure if that card's any good in this type of deck, though.

I kinda like the Ball Lightning s, thanks though. The Swiftspear also doesn't have trample soooo

Elemental Appeal ? Its still pretty good even without kicker.

Eh I second the move to add Monastery Swiftspear . It doesn't need trample, half of the time it will get attacks by just because of its speed. She is pretty much Tarmogoyf for red, with enough spells she can sometimes be worse. You could drop Goblin Guide for her over Ball Lightning if you want to keep those, cheaper deck and nearly as efficient. Not giving the opponent free land could be a big deal. I would also just drop Teetering Peaks . They are not really speeding you up since they come in tapped. This way you could drop down to tighter list of 18 mountains. There are some other lands that could be used such as fetches in combination with Grim Lavamancer . So I would drop elementel appeal and koth, swap 4 goblin guides for monastery swiftspear, add in some number of fetches for red that you own, and throw in 3 grim lavamancers. Magma Jet is also not a bad card for scrying 2 since burn depends so heavily on top decking. I'm really more familiar with burn in legacy though. Honestly burn never should want or expect to see 4 lands necessarily.

Just thought about this card, Genju of the Spires if you like how interesting that could be. Spark Elemental could be decent and Thunderbolt happens to be modern legal also. I think some number of Anger of the Gods or Pyroclasm is needed in the side. That is all I can think of at the moment.

Genju of the Spires is actually a pretty bad card. The reasons for this is that the card doesn't give trample, the sole reason why Ball Lightning is good. It also is using up two cards so when it gets chumped, bolted, pathed or bladed you are losing two cards worth of material when you aren't losing anything to Ball Lightning since it would die anyways.

Thunderbolt is pretty bad, as there are a lot of better alternatives to just plain 3 damage for 2 mana that doesn't target creatures. Magma Jet is one as it filters your next turn.

I just had the Teetering Peaks in there to playtest and forgot to take them out after I realized they screwed me over. I think I'm going to add Swiftspears in for the Goblin Guide s. I've already got Hellspark Elemental so I think I'll leave Spark Elemental out for now. All the other suggestions I'll consider, thanks guys (and girls lol)

Well with genju you don't necessarily lose 2 cards, and even though it doesn't have trample you do not have to activate it and swing with it either. I ran a singleton in my burn deck for awhile it can actually do some work at times, a single hit from it is brutal. Anytime the animated land dies you get it back in your hand, if it got pathed then you lose genju but you get another land anyways to replace it. Pretty much the same argument for the most part of losing a man land to removal.

Also you said Thunderbolt doesn't target creatures which is funny because it can do 4 to a flier. I guess Lightning Strike would be better but 3 damage to the face for 2 is what you are going to be doing with it anyways. Actually in the case of Restoration Angel thunderbolt would be perfectly fine. I would probably go down on Keldon Marauders to 2-3. It is really only great when it gets to swing, just ok if it gets removed. Also it seems like the instants are kind of low.

Just realized that fetches would help this deck as it stands right now too because of Searing Blaze . Right now you are only going to spend 2 at sorcery speed if you are dropping a land. Fetching a land and burning for 3 instantly is what we need to be doing with it. So if you keep searing blood, and add fetches, Grim Lavamancer would naturally fit well there too.

Well fetches are expensive otherwise I would put them in