Scizor

At first glance, Scizor might seem like a potent threat; it has only one weakness, it's considerably strong when it sets up with Swords Dance, and it efficiently uses strong priority. Compelling as these reasons may be, Scizor is, simply put, a less-than-mediocre Pokemon in Doubles OU. Despite it having only one weakness, this same weakness leaves it immediately exploitable for any Fire-type or anything with Fire-type coverage, either of which is commonly found on most teams. Common Water-types also threaten it to a lesser extent by virtue of resisting Scizor's Bullet Punch and being able to do considerable damage or burn it with their own STAB moves. Scizor is also the bearer of lackluster STAB coverage and low Speed, forcing it to rely on Bullet Punch as its main STAB move. Due to this, it is usually outclassed by the likes of Mega Metagross and Aegislash as an offensive Steel-type and by Mega Kangaskhan and Mega Diancie as a Mega Evolution. However, Scizor can still be used, albeit with an ounce of viability. It can become a somewhat threatening setup sweeper with Swords Dance and its strong priority boosted by Technician. Furthermore, being primarily a priority attacker, it can avoid being beaten by opposing forms of speed control, and it still beats Mega Diancie.