Here is a Heatran set I've been using to great success.
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Sub-Salac Sweeper
@ Salac Berry
Timid - Flash Fire
4 HP, 252 SpA, 252 Spe
<ivs - 31,22,30,31,31,31>
- Fire Blast
- Earth Power
- Hidden Power Ice
- Substitute
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This Heatran works wonders in this fast paced metagame. Heatran is the most common pokemon, and without a doubt the most commonly used set is the Timid Choice Scarf sweeper. Because of this, when a Heatran switches in, almost all players automatically assume it is Choice Scarfed. Use this set as offensively as you would a ScarfTran and you are guaranteed to have your opponent believe it is. For example, switching Heatran in to revenge kill Shaymin, Weavile, Infernape, etc is exactly how this set is meant to be played. In the mid-game this Heatran uses a single attack at a time to scout out counters, before switching out, acting just as a ScarfTran would. Your item won't give your deception away like Life Orb would.
Despite its effectiveness at mid game clearance, it is the end game when its bulky water counters have been elminated that this Heatran really shines. Use Heatran's brilliant typing to switch in on a resisted move. Imagine the look of horror on your opponent's face when they switch out to their Salamence from their Heatran, and instead of the expected Earth Power they are facing a Substitute. Heatran can then Substitute down to 25% health to activate Salac Berry, keep the substitute, outspeed Mence and OHKO with HP Ice. Then subsequently you use the luxury of being able to switch your moves to Earth Power their Heatran into oblivion, before sweeping the rest of their beliguered team with Fire Blast.
There are two factors that contribute to making this set so effective. One is the natural inclination of players to assume you are using ScarfTran, and if played correctly this set will seem exactly like it until the end game. Secondly, the thing that undos most SubSalac sets is that they get prioritied into the ground - at 25% health almost all pokemon fall to even a weak priority attack. Heatran's excellent typing, however, affords it a resistance to nearly every priority attack seen in the OU metagame. Quick Attack, Bullet Punch, Extremespeed, Shadow Sneak, Ice Shard and Sucker Punch all bounce harmlessly off its fiery steel hide. Even the dreaded Scizor's +2 Atk Life Orb Bullet Punch does a maximum of 24% to this Heatran, so without a crit it cannot OHKO. The only things Heatran needs to watch out for once it has set up is Aqua Jet, Mach Punch, and Vacuum Wave.
The IVs are a legit spread that allows your HP to be divisible by 4, which means Salac will activate on the fourth sub. It also gives you HP Ice 70, and in total you will only lose 1 Def point.
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So what do people think? Suggestions and criticisms are most welcome.
Thanks.