I has nice stats all around and great typing, and can be a quite effective specially or phisically based mixed sweepers with cheer up to hit pokeoon like Hippowdon and Steelix harder on their weaker special defensive sides and or pokemon like Mantine with stone edge on its weaker defensive side, though it may be less appealing that SD or CM sets, but it can still work out, like:
Specially Based mixed booster
Kobaruon @ Life Orb/ Expert Belt
Naive
252 Speed/ 64 Att/ 192 SpAtt or
252 SpAtt/ 64 Att/ 192 Speed
~ Cheer Up
~ Close Combat/ Sacred Sword
~ Flash Cannon/ Volt Change
~ Hidden Power Ice/ Hidden Power Grass/ Hidden Power Ground/ Focus Blast
1 Cheer Up boosts you up to a respectable 396 special attack and a nice 348 Attack, leaving you with some nice power to start a sweep. Close Combat or Sacred Sword are for hitting Blissey and are a realible form of STAB. Flash Cannon also offers STAB coverage and hits bulky Rock Types or their usually lower special defensive side. But since it's not too good for coverage, Volt Change hits Bulky waters like Slowbro pretty hard and allows you to escape threats like Shadow Tag Shandera or scout. HP Ice hits Dragons and Bulky Grass types like Tangrowth, but mainly the fomer. HP Grass also works in conjunction with Flash Cannon to hit Bulky Waters, along with Swampert, Quagsire, and Gamageroge, who otherwise won't take damage from Volt Change. Hidden power ground hits Shandera and other fire types that can cause trouble. Focus Blast hits Steelix and Nattorei harder than CC or Sacred Sword, but limits your coverage significantly. If you want to hit harder and still hit a good speed, switch Speed and SpA evs so it looks like 252 SpAtt/ 64 Att/ 192 Speed.
And of course, with it's larger physical movepool, it makes a good physically based mixed sweeper too
physically based mixed booster
Kobaroun @ Life Orb/ Expert Belt
Naive
252 Speed/ 192 Attack/ 64 SpA or
192 Speed/ 252 Attack/ 64 SpA
~ Cheer Up
~ Close Combat/ Sacred Sword
~ Stone Edge/ Iron Head
~ Hidden Power Grass/ Ice/ Focus Blast
Pretty the same set as before, except the EVs are adjusted for physically sweeping. The first two slots are pretty much self-explanatory, while Stone Edge hits threatening fire types, like Uragamoth and Shandera. However, Iron Head can get some nice flinches along with STAB. The Hidden powers are for they're same reasons as explained in the set above, and Focus Blast hits Steelix hard, but, again, you lose coverage.
They will probably be discarded for CM or SD sets, but they can do very good against unsuspecting/ unprepared opponents.