Okay, I've been using this Rapidash for a while, and I've managed to peak at 1344, just short of silver tier. Its primary purpose on my team is to absorb Will O Wisps aimed at its teammates (Golem, Samurott, Sawk, Skuntank) and to get rid of their users, as well as Tangela. So far, it's been doing a really good job against Misdreavus and Weezing, and it's handy for taking on Fire types in general. After Rocks, Magmortar even dies to Flare Blitz. o_O
Rapidash (F) @ Life Orb
Trait: Flash Fire
EVs: 252 Atk / 4 SDef / 252 Spd
Hasty Nature (+Spd, -Def)
- Flare Blitz
- Double-Edge
- Overheat
- Morning Sun
Overheat is there to help Rapidash get past physical walls like the aforementioned Weezing, and is helpful when I need a Fire attack that doesn't induce a lot of recoil. Double Edge is there so that I can hit Fire types other than Magmortar for decent damage, and also gives me a neutral hit on Water types, although I should probably be using something like Low Kick, Wild Charge or HP Grass over it. Although it dies quickly, it kills pretty quickly too.
I tried using Megahorn over Double-Edge, and it ended up costing me silver, so meh.