Bought the Relentless Rush intro deck mainly because I loved playing with Impact Tremors in draft. This is my modified version to play with.
Here are the changes I made and why.
+1 Impact Tremors - More ping for the dashers
-1 Vial of Dragonfire - Too slow and I have burn to cast.
+3 Reckless Imps - Turn 2 flying dasher.
-3 Kolaghan Skirmishers - Less of the same.
+2 Roasts - Cheap removal.
-2 Kolaghan Aspirants - Just feels like an odd fit.
+2 Vaultbreakers - Another creature to dash with a dump/draw ability perk.
-2 Tormenting Voices - See above. Had plenty of other 2 drop spells anyway.
+1 Thunderbreak Regent - 4 drop, 4/4 flyer with a 3 hit perk.
-1 Kolaghans Monument - 3 plus 6 equals "No Thanks"
+2 Ultimate Prices - Cheaper than Flatten, will sideboard if needed.
-2 Flattens - Like it, but I hope to be dropping creatures big enough to kill a 4 (plus I have Roast already)
+1 Outpost Siege - For mid play, Khans if my creatures bite it early, Dragons if I still have a hand full of dashers.
-1 Defeat - Making room, less of the same.
+2 Bloodfell Caves - makes sense to ditch the Evolving Wilds anyway. Also pulled one of each basic in favor of the dual lands.
+1 Dragonlord Kolaghan - Not my favorite Dragon but I think it could prevent some annoying planeswalker from showing back up.
As far as sideboard goes I'm mainly concerned with aggro / token decks, using Virulent Plague, Seismic Rupture, Mob Rule and Crux of Fate if needed.
Fighting a Mid range or ramp deck with something huge I planned on using Act of Treason to smack them with their own stuff, as well as Mob Rule and Crux of Fate again.
Flatten and Merciless Executioner, Self-Inflicted Wound also as need if my other stuff isn't working.
Adding in the extra Duress's for the control decks.
There is some stuff I'm questioning. - I'm thinking Mob Rule would be a better replacement for Dragonlord Kolaghan in this deck. Just seems like a more likely win con when it's getting close. - Lightning Strike vs Twin Bolt. I like that I can split up the Twin but wondering how often it's the better choice.- Also thinking about bumping up the Ambuscade Shaman and Warbringer up by 1 each and ditching the Kolaghan Forerunnerss. Trample sounds nice but the power is usually around 2 or 3 when he gets played the majority of the time, but cheaper dash costs and +2/+2 for all my guys makes me happier.