Infernape, Staraptor, Roserade, Vaporeon, Mamoswine, and Luxray
Flamethrower or any other really good fire type, I just put that for its mix of accuracy and power, as well as his STAB move. Grass Knot provides great coverage, especially when it comes to facing Bertha. Close Combat is just awesome, I mean, it's a great mix of power, as well as a great STAB move. Finally, Shadow Claw for a drop-in psychic type, and just in case measure against Lucian.
Close Combat, again, is just awesome, as well as for coverage against a drop-in rock type or ice type. Brave Bird is for his STAB move, and again is ridiculously powerful, in exchange for a little health. Steel Wing for overall attacks, mostly. U-Turn for Scouting, and is always helpful.
Roserade (Natural Cure)
-Magical Leaf/Giga Drain/Energy Ball
Toxic Spikes are just generally appreciated, and rarely used, it seems. I do have a choice for his general grass STAB move, and it really just depends on what you want: accuracy (Magical Leaf), annoyance (Giga Drain), or just general power(Energy Ball). Sludge Bomb is another STAB move, just in case you couldn't put Toxic Spikes down. Finally, Shadow Ball, again for a drop-in psychic type.
Vaporeon (Water Absorb)
Due to his ridiculous HP/Sp. Atk mix (130/110), Vaporeon is a major threat that has to be one of the best in the game. Surf is there just for sheer power, along with his STAB move. Swift is there just in case somebody drops in with Double Team, and is just helpful in little niches. Ice Beam is just amazing, and can't really be topped. Finally, to make things even more annoying for the opponents, Substitute is there in case you suspect for ridiculously powerful enemy moves, for example: Cynthia's Garchomp, or something along that line.
As Mamoswine might not be the quickest in most fights (Base 80 Speed), Avalanche helps for revenge-killing opponents after a hit. Earthquake, like Close Combat, is just an awesome move, especially with his STAB bonus from it, as well. Rock Slide for another good move against Flint's team, just in case. Finally, Stealth rock for trade-out damage fun against other powerful opponents.
Luxray is in a somewhat awkward position as an offensive electric type, as he does not receive the best moves, and, if you are like me, you were not paying attention to his Sp. Atk, he really suffers when it comes to his STAB moves. Thunder Fang has a chance for both flinching as well as paralysis. Crunch for some coverage, as well as a helpful little chance for Defense-lowering assistance. Iron Tail for ice and rock types, and if you suffer going against Cyrus's Gyarados, then you will want Magnet Rise, due to Gyarados' Earthquake.
All-in-all, these are the materials needed for this list:
-4 Blue Shards
-6 Green Shards
-6 Yellow Shards (all for Vaporeon's Swift and Luxray's Magnet Rise, Snowpoint City)
-Water Stone (for Vaporeon, Route 213)
-Shiny Stone (for Roserade, Iron Island B3F)
-Heart Scale (for Mamoswine to evolve, you need to teach him AncientPower)
-TM 35 Flamethrower, Fuego Ironworks
-TM 86 Grass Knot, Eterna Gym
-TM 65 Shadow Claw, Hearthome Gym
-TM 47 Steel Wing, Route 209
-TM 89 U-Turn, Canalave City
-TM 36 Sludge Bomb, Galactic Veilstone Building B2F
-TM 30 Shadow Ball, Route 210
-TM 13 Ice Beam, Route 216
-TM 90 Substitute, Old Chateau 2F
-TM 72 Avalanche, Snowpoint Gym
-TM 80 Rock Slide, Mt. Coronet [middle] 2F
-TM 76 Stealth Rock, Oreburgh Gym
-TM 23 Iron Tail, Iron Island B2F