To all of you people saying "Aerial Ace because it gets STAB", that is an extremely naive argument that ignores the dual factors that Aerial Ace has pathetic base power (60, which means Stone Edge does more after even STAB) and poor type coverage (Ice and Rock both work better with Ground). Aerial Ace is useless for the standard Heracross, which is Choiced and never getting past a well-played Gliscor anyways, and a simple Earthquake usually breaks Breloom's Substitutes. Any Fighting Pokemon can either get smothered to death by Earthquake or beat Gliscor with Ice Punch; there is little to no gray area except in the instance of Swords Dance Heracross. Additionally, Aerial Ace does a negligible amount of damage on the standard Grass types, which are Celebi and Tangrowth, and Stone Edge covers Bug Pokemon like Yanmega better. Overall, I like Ice Fang the most if I were to use a secondary attack because of the enormous threat Pokemon like Garchomp pose, but usually I run a full-support Knock Off / Earthquake / Roost / Stealth Rock set. U-Turn is also a cool move to use if you want.