Cobalion @ Leftovers
Ability: Justified
EVs: 4 HP / 252 Atk / 252 Spe
Jolly Nature
- Close Combat
- Iron Head
- Swords Dance
- Stone Edge
I wanted this team to have a sort of bulky offense flair, and Cobalion immediately came to mind. He has the defenses to provide coverage and offensive coverage throughout the entire game, and then can set up and sweep once his threats have been eliminated. Close-Combat hits extremely hard, and there's few things that resist it, while Iron Head is a safer yet still powerful option. Stone Edge makes a dent in flying- and fire-types like Entei and Crobat. Justified allows him to take some dark-type attacks from Jellicent's switch-ins.

Hydreigon @ Life Orb
Ability: Levitate
EVs: 4 Atk / 252 SpA / 252 Spe
Hasty Nature
- Draco Meteor
- Dark Pulse
- Fire Blast
- Roost
Hydreigon has wonderful synergy with Cobalion, checking bulky Psychic-types like Cresselia, offensive Ground-types with Levitate, and pesky Ghost-Types that are immune to fighting moves. Roost makes sure that Hydreigon's offensive presence can remain throughout the entire match, also negating the ill-effects of Life Orb. Meanwhile, Cobalion can easily switch in on the bug and ice moves aimed at Hydre,  also applying pressure to Fairy types with Iron Head.

Jellicent @ Leftovers
Ability: Water Absorb
EVs: 252 HP / 252 Def / 4 Spe
Bold Nature
- Recover
- Scald
- Will-O-Wisp
- Taunt
Jellicent is one half of this team's defensive core, and makes an incredible teammate to Cobalion and Hydreigon. The big jellyfish loves taking Scalds for Cobalion due to Water Absorb, and can take care of the ground- and fire- types that threaten Cobalion with Scald. Jellicent is also immune to fighting-type moves, one of Hydreigon's most prevalent weaknesses. Burn and Taunt support are wonderful additions to an already great defensive option, as is Recover. Most of the attacks that threaten Jellicent are special, so I went for Defensive investment instead, but Jelly's SpD is nothing to laugh at even with no EVs.

Florges @ Leftovers
Ability: Flower Veil
EVs: 252 HP / 224 Def / 32 SpD
Calm Nature
- Wish
- Protect
- Moonblast
- Aromatherapy
Florges forms the other half of the defensive core, giving the team a fantastic desperately option against Dragons. With a little special defense investment to add to her already amazing base SpD, I can afford to put the rest of the EVs into Defense, making Florges a special wall that can also take many physical hits. The bulkier offensive members of the team and Jellicent love Wish support, and the addition of Aromatherapy is what makes Florges the best healer in the tier. With Cobalion and Jellicent, poison-types are easily taken care of, and Cobalion's Close Combat, Hydreigon's Fire Blast, and the next member of the team ensures that steel-types can't cause any trouble.

Rotom-Heat @ Choice Scarf
Ability: Levitate
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Volt Switch
- Overheat
- Hidden Power [Ice]
- Trick
Rotom is an extremely fun and effective revenge killer, nuking steel- and grass- types with Overheat and keeping the momentum going with Volt Switch. Hidden Power Ice gives Rotom an option against M-Salamence, Zapdos, and Ground-types. Trick can cripple defensive/cleric Pokemon on the other team, and Rotom can function without the scarf if needbe to become more of a wallbreaker.

Roserade @ Life Orb
Ability: Natural Cure
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Spikes
- Sludge Bomb
- Leaf Storm
- Sleep Powder
Roserade provides the team with the few things it was missing- hazards, and an answer to bulky-waters, fairies, and M-Swampert.