DarkTyphlosion is right. I was wondering myself but if you have Sheer Force and a life orb you will not take life orb recoil. Example: Nidoking with sheer force uses Sludge Wave with 95 base power, goes up to 142.5 with STAB, with Sheer force added that's 185.25 and with the life orb...that's a staggering 240.825! Which means you will do tonnes of damage. I used Sludge wave as an example, since it has a secondary effect (poisoning the foe) Earthquake won't get the sheer force bonus as it has no secondary effect. As a result you will take life orb damage. Hope this helps! Now I need to get one myself! >:-)