>>234450254 SpA Garchomp Fire Blast vs. 252 HP / 4 SpD Skarmory: 176-208 (52.6 - 62.2%) -- guaranteed 2HKO
252 Atk Garchomp Fire Fang vs. 252 HP / 252+ Def Skarmory: 82-98 (24.5 - 29.3%) -- 99.9% chance to 4HKO
252 Atk Garchomp Fire Fang vs. 252 HP / 88+ Def Ferrothorn: 192-228 (54.5 - 64.7%) -- guaranteed 2HKO after Leftovers recovery
252 Atk Garchomp Fire Fang vs. 252 HP / 88+ Def Ferrothorn: 192-228 (54.5 - 64.7%) -- guaranteed 2HKO after Leftovers recover
252 Atk Garchomp Fire Fang vs. 252 HP / 252+ Def Whimsicott: 114-136 (35.1 - 41.9%) -- guaranteed 3HKO
4 SpA Garchomp Fire Blast vs. 252 HP / 4 SpD Whimsicott: 168-198 (51.8 - 61.1%) -- guaranteed 2HKO
you score some important 2HKOs, but keep in mind this is without life orb and you beat ferrothorn either way but avoid his barbs and possibly helmet, and whimsicott is uncommon I really only included him since he resists both your stabs. It also comes with the small caveat that you're slightly more vulnerable to special attacks and have a more inaccurate fire attack.
Use fang if you know skarmory and ferro's recoil is a non issue, or if you use SD.
