Moltres


Type: Fire / Flying
Base Stats-
90 HP / 100 Atk / 90 Def / 90 Spd / 125 SAtk / 85 SDef

Weaknesses: Rock(x4), Water, Electric
Resistances: Bug(x4), Grass(x4), Fire, Fighting, Steel
Immunities: Ground

Abilities-
Pressure: While facing Moltres, Pokemon lose 2 PP for each move used instead of 1.

Choice Specs

Moltres @ Choice Specs
Ability: Pressure
EVs: 16 HP / 240 Spd / 252 SAtk
Modest Nature (+SAtk, -Atk)
- Overheat
- Air Slash
- Hidden Power [Fight]
- U-Turn / Flamethrower

Despite having a small offensive movepool, Choice Specs Moltres is going to hurt a lot of things.

A STAB Choice Specs Overheat coming off 125 Base SAtk will simply destroy, even doing 40-47% to a standard Blissey.

Air Slash is another STAB move, that is useful for hitting things that Overheat cannot, such as Houndoom and Swampert. It will nearly OHKO Houndoom, and does 53-63% to Swampert, easily scoring a 2KO.

Hidden Power [Fight] is almost a necessity here, because it is able to hit Tyranitar and Heatran, two of Moltres' potential counters.
You may be tempted to put HP [Ice/Grass/Electric] here: that is a bad idea. Air Slash will 2KO most of the Pokemon you would use those Hidden Powers for anyway, such as Salamence, Gyarados, and even Slowbro.

Last spot is filler. U-Turn is good for scouting counters, while Flamethrower will give you consistent damage.

Sunny Day

Moltres @ Life Orb / Heat Rock
Ability: Pressure
Evs: 4 HP / 252 Spd / 252 SAtk
Modest (+SAtk, -Atk)
- Sunny Day
- Fire Blast / Flamethrower
- Solar Beam
- Hidden Power [Fight/Ice] / Roost / Morning Sun

lol Solar Beam.

The first thing you'll need to do is set up a Sunny Day. This will seriously power up your Fire move, giving Fire Blast the potential to 2KO Blissey, if you are holding Life Orb. If you would like more reliable damage, you can use Flamethrower instead.

Sunny Day also lets Moltres fire off Solar Beams (which he finally gets!) without having to charge it, letting him do serious damage to Water and Rock types trying to wall him.

Hidden Power [Fight] is the first option for your last move because, more often than not, Tyranitar will switch in on you, canceling out your Sunny Day, and not letting you use Solar Beam freely anymore, at which point, you'd use HP [Fight] on him.
Hidden Power [Ice] is also an option here for the Dragon types who will also wall you, particularly Garchomp.
Roost & Morning Sun are there for recovery if you want to hang around longer, but generally aren't the best option.

As for the item, the best choice is Life Orb, which will let you 2KO Blissey with Fire Blast in the Sun. Heat Rock is another good choice, as it'll keep the Sun around longer without you having to use Sunny Day again.

Bulky-ish

Moltres @ Leftovers
Ability: Pressure
EVs: 188 HP / 228 Spd / 92 SAtk
Timid Nature (+Spd, -Atk)
- Flamethrower
- Hidden Power [Fight / Grass / Electric / Ice]
- Roost
- Will-o-wisp

This is the best Moltres can do when it comes to a support role.
Will-o-Wisp is very very handy to get the burn on things like Tyranitar and Gyarados, seriously hindering their attack power as well as depleting their HP.
Roost is for HP recovery, of course.

Attacking moves are the same as the previous sets.

Other Options:
I've already mentioned pretty much everything worth mentioning.

Toxic can be used for support, and to nail bulky waters, but it's kind of "eh" otherwise.

Rest+Sleep Talk is an option, but not a very good one.

EVs / Nature:
240 Speed on the first set gives you 276 Speed, which lets you outspeed max speed adamant Heracross (270), as well as other things that are trying to out speed max speed adamant Heracross.

188 HP on the "Bulky-ish" set lets you get maximum Leftovers recovery.

Counters:
Stealth Rock. Set up Stealth Rock, and watch as Moltres takes 50% damage everytime it switches in.

As for actual Pokemon, Regirock in a sandstorm is an excellent counter. It is resistant to all Moltres' STAB moves, and doesn't really fear any Hidden Power thanks to his great Special Defense.

Same goes for a Thick Fat Snorlax, though he doesn't resist Air Slash.
Neither like getting Will-O-Wisped.

Blissey can work, but fears a Life Orb Sunny Day Fire Blast, which can 2KO her.

Tyranitar will ruin the Sunny Day set, and pretty much every other Moltres set as long as it doesn't switch in on HP [Fight] or Will-O-Wisp.

Heatran loves to switch in on Fire moves, and resists Air Slash, but fears HP [Fight].

Milotic and Suicune can take him on thanks to their high Special Defense.

Opinion:
Moltres has a lot of things working against it, such as a 4x Stealth Rock weak, and lack of a good movepool.
However, it is still a force to be reckoned with. Even without a great movepool, Moltres covers a lot of stuff with what he does have, and as long as he is teamed with a Rapid Spinner, SR shouldn't be too much of a problem.