Originally Posted by Fat BlackLight
Roserade being able to run a full out offensive Spikes set ŕ la Leaf Storm is, imo, the most notable thing for OU. Conk with Iron Fist will be decent, but it doesn't give Conk any real new things it can do. Roserade, on the other hand, has a new niche, although it does have competition with Deoxys-D for a spot, and we all know that Deo-D is completely solid when it comes to Spiking. Still, Roserade has better typing, imo, so it could see some use for a neccessary resist.
Yes, I would agree that Roserade poses some sort of competition with Deoxys-D for a lead Spiker role. However, I feel like Deoxys-D has the upper hand in the contest. The only notable benefits that Roserade receives are that it can use Sleep Powder to disable unwary foes, and hit opponents hard with Leaf Storm. Deo-D doesn't have access to Sleep status (though it can use Thunder Wave, arguably more useful), but it can use Psycho Boost, a move the same as Leaf Storm in all but type; however, Deo-D's mediocre base 70 Special Attack pales in comparison to Roserade's base 125. Deoxys-D, though, is bulkier, allowing it to live more hits. It also has access to the coveted Stealth Rock, meaning it's not limited on the type of hazards it can lay down. It can also use Taunt and Magic Coat, both valuable options for a lead position Pokemon that Roserade lacks. All in all, I'd say Deoxys-D outclasses Roserade by a slim margin, though the latter is still definitely worth using.
Iron Fist Conkeldurr isn't all that notable, since Guts is by far its best ability, allowing it to get a boost from status like Burn, instead of being crippled by it like most physical attackers. Despite the extra kick for Conk's Drain Punch, Mach Punch, and Ice Punch, I expect we won't see much of this ability.