I chose to base a team around Sub SD Cobalion, which is a set I've been a fan of for a while, as well as Cobalion itself. I then added Pursuit Mega-Aerodactyl to trap Chandelure and Victini, two common stops to the set, while also providing solid type synergy, resisting Fire and Ground. I decided to run Aqua Tail to hit Bulky ground types like Hippowdon or Donphan that can prove to be troublesome to Cobalion, with an exception of Swampert. As these two both had trouble with bulky water types like said Swampert, I decided to add Life Orb Roserade with Toxic Spikes. After adding these three, I decided to create a balanced team, and added a core of Florges Swampert and Forretress. The sets were all standard, and they were all able to check common threats such as Haxorus, Hydreigon, Victini, Mienshao, etc. The combination of Roserade, Forretress, and Swampert also let me have both Spikes, Toxic Spikes, and Stealth Rocks. This variant of the team was stuck in the 1550s or so for some time, so I decided that it needed some change. I tested out a lot of changes, although the final result ultimately was the same thing except for one simple change: Life Orb Roserade to Nasty Plot Celebi. I'm not sure what if it was this, or if it was the fact that I just got more used to the team and played better, but this final result was able to take me to the mid 1600s, and I could probably go higher if I tried, since I stopped when I reached 1642. Although Celebi let me check Psychic types like Cresselia, Reuniclus, and Alakazam better, while also hitting Crobat that could expect a defensive set and defog my hazards away. While being a check to Crocune that wasn't trapped by Dugtrio like Roserade could be, I didn't come across that scenario at all if I remember correctly. Although that is a plus to using Celebi over Roserade. It also gave me a second set up sweeper alongside Cobalion, and was a better answer to Tentacreul, who was problematic to Cobalion+Aerodactyl+Roserade (I was using Hp Ground Roserade at the end of using Roserade on the team though because it hits Chandelure and Tentacreul, both being good Cobalion) stops. Overall, the team was quite fun to use, as I like Cobalion a lot, and offensive Celebi is both underrated, viable, and quite fun to use. I forgot to save some good replays of the team in action, although I do have a couple, yet my opponents in them weren't that good and I didn't play that well in others and didn't get to show how the team functions as well as I would like to. I'll try to get some replays versus people in the chat right now though, and I may as well post the few I have.
Replays:
http://pokemonshowdown.com/replay/uu-171015998
http://pokemonshowdown.com/replay/uu-171014659
http://pokemonshowdown.com/replay/uu-169414247
http://pokemonshowdown.com/replay/uu-171302421
http://pokemonshowdown.com/replay/uu-171567209
