Heatran (M) @ Leftovers
Flash Fire | Calm | 244 HP / 44 SDef / 220 Spd | 0 Atk
Substitute | Protect | Torment | Lava Plume
Tormentran is extremely rare nowadays, yet the set is still quite effective, although not as much as before, sadly. Due to Heatran's many resistances, there are not too many super effective moves that actually can hurt Heatran. Ground, Water, and Fighting. Many Pokemon only carry one move to Heatran, and by using Torment, they cannot use the same move twice in a row. I can stall out using Substitute and Protect, Subbing up when my opponent's move is useless against me, and Protecting on the turn that my foe is actually going to use the super effective move. Lava Plume is there to spread status, STAB, as well as not becoming complete Taunt bait. I understand opposing Heatran wall me, but that is easily solved by another Pokemon on my team, who you will see later on. EVs allow Heatran to hit a Leftovers number, as well as outspeeding Jolly Tyranitar.
Jirachi @ Leftovers
Serene Grace| Careful | 252 HP / 236 SDef / 20 Spd
Stealth Rock | Body Slam | Iron Head | Wish
I know you guys hate this thing. It's insanely annoying to face, yet so fun to get the opponent ready for a ragequit. Yeah, its a basic ParaFlinch Jirachi, who sports a little better special bulk on my team than Heatran does, due to its main job. Stealth Rock is my hazards, and it's always nice to stack a bit of damage each time a Pokemon switches in. Body Slam has a 60% chance to paralyze my opponent, and when combined with the 60% chance to flinch with Jirachi's STAB Iron Head, it can slowly piss off the opponent, often rendering it unable to move. The Paralysis support helps the general slowness of the team, such as Breloom and Gliscor. Wish support is used to heal off weakened teammates, especially Heatran, who now has a lack of bulk.
Gengar (F) @ Black Sludge
Levitate | Timid | 4 HP / 252 SAtk / 252 Spd | 0 Atk
Substitute | Disable | Shadow Ball | Focus Blast
EDIT: TRYING TAUNT.
After noting a Fighting and Ground weakness unchecked, I decided on a Gengar, who still can manage to piss people off, while maintaining those immunities that I need. You've all faced SubDisable Gengar before: Gengar Subs up on the switch or before a move, and when the opponent finally executes a move I badly do not want touching my Pokemon, I Disable it for 5 turns. The rest of the moves, Shadow Ball (which is STAB) and Focus Blast, provide perfect neutral coverage throughout all tiers.
Breloom (M) @ Toxic Orb
Poison Heal | Adamant | 12 HP / 244 Atk / 252 Spd
Spore | Substitute | Seed Bomb | Focus Punch
Go ask Leboss about how he feels about this thing. He absolutely detests it. Due to the paralysis support that Jirachi has with Body Slam, as well as the Sleep support that Breloom can deliver with Spore, this thing becomes an absolute monster. Poison Heal is great; it allows me to recover health from the Substitutes it uses to perfect to its greatest potential. After my opponent is crippled, or during a switch, I Sub up, and prepare to turn games around. Focus Punch is absolutely amazing on this guy - 150 base power, STAB, as well as coming off a 392 attack stat? If I encounter a Ghost, a Seed Bomb will usually deal quite a bit of damage, even to those who resist it.
Gliscor (F) @ Leftovers
Poison Heal | Impish | 244 HP / 40 Def / 224 Spd
Substitute | Protect | Earthquake | Toxic
Continuing down the annoying line. Gliscor is an absolute pain in the ***, due to one of its greatest tactics: SubProtect. This is especially dangerous when Gliscor has managed to get Toxic onto the opponent's Pokemon, allowing Poison to overcome the opponent, while Toxic Orb's inflicted Poison allows me to shrug off Substitute damage quite nicely. Earthquake, which is STAB, is there to deal passive damage to Pokemon while I'm SubProtecting, or when I'm facing a Steel Pokemon.
Rotom-W @ Leftovers
Levitate | Modest | 232 HP / 56 SAtk / 220 Spd | 2 Atk / 30 Def
Volt Switch | Hydro Pump | Will-O-Wisp | Hidden Power [Ice]
I needed a good Special Pokemon, and I badly needed coverage, especially in Electric and Ice. Rotom-W's bulky attacker set proved most beneficial to me, as it spread out the coverage for me, as well as providing useful resistances to Ground, Water, and Fire. Rotom-W accomplishes many offensive and defensive threats, tanking Specs Keldeo's Scret Sword, Modest Thundurus-T's Thunder, LO Lucario's ExtremeSpeed at +2, and many more. EVs allow Rotom-W to outpace Jolly Breloom, and enough Special Attack to OHKO certain threats, especially when under rain. Volt Switch allows me to grab momentum, as well as being STAB. Hydro Pump is STAB also, and hits the Fire types my team can't basically do anything against hard. Will-O-Wisp cripples Physical sweepers, bolstering Rotom-W's Def. Hidden Power [Ice] is some needed Ice coverage, and strikes Dragons and Gliscor hard.