I must admit that this guide is mostly for the Third Generation, which is RSE/FRLG. If you are wondering why I don't include RBY and GSC information, the answer is, sections I-V includes most of RBY and GSC information. However, from now on, it will almost be stricly RS/FRLG. Also, it is extremely hard to go back and forth between the three because there were many changes and reading the guide would be very confusing. Every time a new generation comes out, there were not only additions--there were many modifications as well, including most of the game mechanics. The worse was from RBY to GSC. RBY is a whole new world to us now, because everything is so simplistic and so different. Some notable changes were changes in Type Alignment Advantages (and additions), Hidden Power, the change of most moves, the collapse of the Psychic type, item attachment, as well as many moves additions. RSE/FLRG introduces Effort Values, new strategies (this was a tough one), Natures, and Abilities. As you can see, this is why the below Move Combinations will mostly apply to the Third Generation. I will try to organize them into the order of most important to least, but if they are listed, then they are important in some way.
If you do not know what a move does, please refer to this page: Smogon
1) Subpunching
If you can predict a switch or a Status Inducing move, the use Substitute and your opponent won't attack you with a damaging attack. Then, you use Focus Punch, dealing 150 Fighting Damage, very successful if you have a high Attack, if it is super-effective or if it has STAB. The hard thing is to predict when to use Substitute. Here is an example:
Turn 1: You send out Starmie.
Opponent sends out Snorlax.
(Starmie isn't going to hurt Snorlax...trust me)
Turn 2: You call back Starmie. You send out Heracross.
Enemy Snorlax uses Curse. Enemy Snorlax's attack rose! Enemy Snorlax's Defense rose! Enemy Snorlax's Speed fell!
(Snorlax will not be staying in for Heracross)
Turn 3: Opponent calls back Snorlax. Opponent sends out Skarmory.
Heracross uses Substitute. Heracross has created a Substitute!
(Skarmory is an effect counter to Heracross, but it's Skarmory who will be taking damage)
Turn 4:
Heracross focuses its energy!
Enemy Skarmory uses Drill Peck. It's super-effective! Heracross' Substitute faded.
Heracross uses Focus Punch. Heracross' Focus Punch dealt 35% damage to Skarmory Skarmory restores its health using Leftovers.
(Heracross did its job)
Turn 5:
You call back Heracross. You send out Starmie.
Enemy Skarmory uses Spikes. Spikes scatter around Starmie!
(Your opponent knows Heracross will switch out)
If you don't follow what just happened, then you will learn by experience anyways. The point is, Subpunching is not a strategy that you take for granted, since it requires much anticipation.
2) BoltBeaming
A BoltBeamer is a Pokémon that has both Lightning Bolt and Ice Beam in its moveset. The good thing is, only Laturn and Magneton resists these two moves, so you can pretty much do decent damage to most Pokémon. Two good BoltBeamers are Regice and Lanturn.
3) EndReving
An EndRever is a Pokémon that uses Endure (End) and Reversal (Rev). If you recall from memory or the link above, Reversal's power increases as your HP decreases. When you Endure a hit, your HP will be at 1, so that gives Reversal maximum power. This is usually used with Salac Berry, and if you recall, Salac Berry raises your Speed when your health reaches 25%. This way, your Speed rises when you Endure and you are probably fast enough to take down your opponent. This strategy can be used for Flail and Endeavor, which does approximately the same thing. Watch out, since if your opponent switches to a Ghost type, then Reversal, Flail, and Endeavor is useless. Sandstorm will also defeat this strategy.
4) SubReving
A SubRever is a Pokémon that uses Substitute (Sub) and Reversal (Rev). Since Endure's accuracy falls to 50% if you Endure twice in a row, you need to predict if your opponent's attack will faint you or not. When you use Substitute, you create a copy of yourself for the cost of 25% of your maximum. Substitute never faints the user, so after four Substitutes, your HP will be extremely low. Note how this works almost like Endure, but you can use Substitute repeatedly without fail (unless no one broke your Substitute, then you just attack the opponent). After four Substitutes, Salac Berry will activate and you can then Reversal, Flail, or Endeavor. A downfall to this strategy, even though it is often considered better than EndReving, are moves that attack multiple times. You will be fainted by moves such as Rock Blast and Bonemerang. A Ghost type can still defeat you, and so can Sandstorm.
5) Stat Changing + Baton Pass
Although this isn't a real strategy, it's here because pummeling you opponent with attacking move isn't going to do. Have some strategies in increasing your stats or decreasing your opponent's stats, because this will be more beneficial for you in the long run. Take Heracross for example. Swords Dance then Megahorn is better than Megahorn then Megahorn.
6) BellyRest
If you do not know, Belly Drum sacrifices half of your maximum HP while maximizing your Attack. If you don't know how much Belly Drum maximizes by, I can tell you that it's enough to OHKO (One Hit Knock Out, or meaning you faint the opponent in one attack) most Pokémon. Belly Drum followed by Rest means that you will replenish your HP sacrificed, making you an awesome Sweeper. Usually, BellyRest involves using a Mint Berry or a Chesto Berry to restore the Sleep Status Effect.
This strategy requires exact timing. If you spot its weakness, taking away half of you HP and giving your opponent a chance to attack isn't fun. This is why most of the time, you have to predict a switch and use Belly Drum. Also, you can induce a Sleep/Paralyze Status Effect, and/or the Confusion/Attract Status Problem. This way, you are lowering the chances your opponent has of attacking, or forcing a switch, giving you a free Belly Drum. Here is an example:
Turn 1: You send out Starmie. Opponent sends out Milotic.
Turn 2: You call back Starmie. You send out Snorlax.
Enemy Ludicolo uses Calm Mind. Milotic's Special Attack rose! Milotic's Special Defense rose!
(Milotic cannot faint Snorlax because Snorlax's Special Defense is too high)
Turn 3: Opponent calls back Ludicolo. Opponent sends out Aggron
(Your opponent hopes to Roar away Snorlax's expected Curses)
Snorlax uses Belly Drum. Snorlax cuts its HP in half to maximize its Attack!
Now, Aggron cannot roar because Snorlax will OHKO it. This is now the realm of guessing work as to if Snorlax will use Return, Brick Break, or Earthquake. If Snorlax can Rest, then it will be almost unstoppable. However, once again, you need to time this. Note that it is best to use this at the end of a battle, when it's more likely that there are less Pseudo-Hazers that could Roar or Whirlwind away your Belly Drumer.
7) Parafusion
Parafusion hurts, literally. This is the strategy of using both Paralysis and Confusion, giving your opponent a 33% chance to attack! This is best used with Seismic Toss since you need a Pokémon with good defenses to be able to survive using both of these moves, and Seimic Toss always deals 100 HP off your opponent no matter what the user's Attack stat is. The last slot is probably Rest, Shadow Ball, or Attract.
8) Swagger + Psych Up, Flatter + Psych Up.
Swagger confuses the opponent and raises its Attack by two stages. Flatter confuses the opponent and raises its Special Attack by two stages. Psych Up copies all of the Status Changes that your opponent has, and if you raised your opponent's Attack or Special Attack, then you can copy it. Note that you do not copy your opponent's Confusion since that is a Status Problem. This is a way to boosts up your Attack or Special Attack if you cannot learn Swords Dance or Tail Glow. Umbreon is a good candidate for Swagger + Psych Up. Its defenses are so high that it doesn't mind raising its opponent's Attack. No Pokémon can legally have both Flatter and Psych Up, so you might want to switch out then Psych Up your opponent.
Note that Psych Up by itself is extremely good. Predict a Belly Drummer, Psych Up, and you'll be Belly Drumed without losing half of your maximum HP!
9) TrickBand
Remember what I said about Choice Band? It raises your Attack by 1.5x but it only allows you to use one attack only until you switch out. Trick switches your item with your opponent's. However, if you Trick Choice Band with a non-Physical Sweeper, then your opponent is forced to use the move that had used against you while you used Trick. Choice Band is great, but not on Starmie and Ludicolo. This strategy will seriously hinder your opponent's strategy.
A good TrickBander is Alakazam, since it has great Speed to allow it to pull it off. Notice that you no longer have Choice Band, so you are not required to use Trick again. It's a neat strategy that requires not a lot of anticipation.
10) Thief
Thief is an interesting move that I don't use much, since it tends to have avery complex strategy. There are only several items worth stealing, and thoseare items that the Pokémon's moveset is depended upon. What I'm saying is, without that item, the Pokémon is technically screwed. This can backfire see,since if your opponent doesn't have that kind of Pokémon, then your Pokémon with Thief is really useless. You can steal Leftovers, but that's about it.
One example is Lum Berry. If you steal Lum Berry then Burn a Gyarados throughWill-o-Wisp, then Gyarados' Attack halves, greatly disabling its Sweeping abilities. Note that Lum Berry will cure any Status Effect inflicted on Gyarados, such as Burn.
Another example is to steal Choice Band. If you recall, it multiplies every physical damage by 1.5x, so you just lowered the Attack of a good Sweeper, like Heracross. Note that the other option for Heracross is Leftovers or Salac Berry, but if you steal Choice Band, then it cannot have Leftovers nor Salac Berry! Heracross is now just a mediocre Sweeper. Be careful though, since you have to switch out your Pokémon using Thief because Choice Band will force it to use Thief again. Also, make sure that the Choice Band stealer is also a Sweeper, so it can actually use Choice Band when it switches in again.
So how do you know if your opponent's Gyarados have Lum Berry or if your opponent's Heracross have Choice Band? You don't. This is why Thief is only used by experts who have great anticipation skills, and yes, it can be very effective.
11) Snatch
This move is evil...very evil. It's similar to Psych Up, but unlike Psych Up, it steals your opponent's Status Changes, not only copy. Also, it can steal Substitutes, surprising those Annoyers. Just wait until Suicune uses Calm Mind 3 times while you act like you don't know what's going on, then use Snatch and leave your opponent crying. Note that Snatch always go second, so you cannot start off a round be stealing someone that was done before. You steal at the end of the round, so make sure to Snatch before your opponent gets a chance to attack.
12) Perish Trapping
As I said before, in RSE/FRLG, this works best with two Pokémon. Those two canditates are usually an Umbreon Baton Passing Mean Look to someone with solely Perish Song and a healing move or Protect. Some good Candidates are Lapras, Wigglituff, Celebi, Altaria, and Misdreavus. In the old days of GSC, Lapras used to Whirlpool to keep the opponent in its place, and Misdreavus used to Mean Look. Now, both of those moves would waste so much time and Lapras and Misdreavus would faint before setting up Perish Trapping.
13) MintyRest, ChestoRest, LumRest
Minty Rest is Rest + Mint Berry attached, and ChestoRest is Rest + Chesto Berry attached. This gives you a free 100% HP Recovery. It's that simple. Use it when you think you will faint (but time it so you don't faint). LumRest is Rest + Lum Berry attached. This is a strategy in the Third Generation because of Will-O-Wisp alone. True that you can Rest the Burn Status Effect off, but if you're a Physical Sweeper, then you certainly don't want your Attack halved.
14) Rain Dance + Thunder (ThunderDance)
An effect of Rain Dance is that Thunder will never miss. Think about it...Lightning appears in storms, right? Anyways, you can have someone from your team use Rain Dance and make your team benefit from it. For example, use water Pokémon, Pokémon with Hydro Pump, Pokémon with Thunder, and Pokémon with the Rain Dish or Swift Swim Trait.
15) Sunny Day + Solarbeam (SunnyBeam)
An effect of Sunny Day is that Solarbeam will not require a charge. Remember that Solarbeam take in sunlight then attack. Now, it just attack because Sunny Day provides the sunlight that Solarbeam needs. You can also include fire Pokémon, Pokémon with Fire Blast, Exeggutor because of the Chlorophyll Trait, and of course, someone with Solarbeam.
16) Leech Seed + Ingrain + Mega/Giga Drain + Leftovers
Ingrain restores HP every turn, and so does Leech Seed and the item Leftovers. Mega Drain/Giga Drain will also restore some HP that you have dealt to your opponent. Obviously, this is an Annoyer/Drainer to the max. Ingrain also means your opponent cannot Roar or Whirlwind you out, because your roots are implanted to the ground.
17) Spore + Focus Punch
Breloom is famous for this. It is fast enough to use Spore, 100% of the time Sleeping your opponent. Then, it uses Focus Punch, because your opponent cannot attack and make Focus Punch lose concentration. That means you have to switch in order to get annihilated, but when you switch, you don't attack, you Breloom gets a free Focus Punch no matter what.
18) Rest + Sleep Talk
This is so annoying, because you have to defeat a Sleep Talker in three rounds or less to prevent it from using Rest again. Sleep Talk attacks while asleep, so coupled with Return and Earthquake, it could cause lots of damage while not being fainted easily.
19) Toxic + Spikes + Sandstorm (TSS)
This is consists of a team that purely annoys. You mainly damage by Toxic, Spikes, and Sandstorm via using Roar or Whirlwind to force being hurt by Sandstorm. However, remember that Sandstorm damages both sides, and Rock, Steel, and Ground Pokémon don't get damaged. Because of this, Suicune can sometimes destroy a TSS team because it has high defenses and is able to Surf its way out of it.
20) Swords Dance/Bulk Up/Calm Mind + Salac Berry
Swords Dance, Bulk Up, or Calm Mind gets you ready to become a sweeper, and when your HP gets low, Salac Berry will increase your Speed so you can attack first with boosted up stats.
21) Agility + Petaya Berry/Leichi Berry
First Agility, then start attacking. When your health is low, your Attack or Special Attack increases and you have a better chance of fainting your opponent easier. Metagross can use this strategy somewhat well.
22) Wish + Baton Pass (WishPass)
First, use Wish. Then, use Baton Pass and pass it to a Pokémon with low health. Since Wish can be Baton Passed, the low health Pokémon will be healed.
23) Pseudo-Passing
Pseudo-Passing is to pass an effect created by one Pokémon to the next without the use of Baton Pass. This is really impossible except for three moves: Reflect, Light Screen, and Safeguard. When these moves are used, a barrier that halves Physical attacks, a barrier that halves Special attacks, and a barrier that stops all Status Effects and Status Problems, repectively, will be formed. These barries will stay for five turns, unless the move Brick Break was performed by your opponent to knock out these barriers. Even if you switch out the user, these barriers still stays, so their effects also stays.
24) Mimic + Imprision
This is pretty much obvious. Use Mimic then select the move that you don't want your opponent to do. Then, use Imprision, and your opponent cannot use that move anymore!
25) Sleep Status Effect + Stat Boosts
When you put your opponent to sleep, rare will it stay in. You expect a switch on the next turn, so this is called a free turn. You can use whatever move without being damaged. Some used this time to use Substitute, some use Calm Mind, some use Swords Dance, and some use Confusion. The point is, this is the perfect time to set up a combination. Milotic can use Hypnosis then Rain Dance. It can also Calm Mind and use Surf the next turn for at least 50% damage (unless it's not very effective). Avoid putting Snorlax or other Pokémon that you think might have Sleep Talk to sleep.
26) Substitute/Protect + Speed Boost
Ninjask has a great Trait called Speed Boost. Every turn, Ninjask's Speed will raise by one stage. The problem is, Ninjask is already the fastest Pokémon in the game (besides Deoxys-Emerald) and it literally cannot take a hit. However, it can Baton Pass the Speed Boots, but first, it needs to survive. Using Substitute or Protect ensures that Ninjask won't take too much damage (in the case of Substitute, 25% of its maximum HP). However, while Protect ensures 100% Evasion, using Protect twice lowers its accuracy to 50%, so it's pretty risky. If you think that Ninjask can take a hit from a Pokémon (by giving it Defense/Special Defense DVs or something) then you can use Protect, Swords Dance, Protect, Baton Pass. It's generally better, however, to use Substitute.
27) Swagger + Screech
As I explained before, when you hurt yourself in Confusion, your Attack stat attacks your own Defense stat. For this reason, Swagger, which raises the opponent's Attack and confuses it, is dangerous. What's worse is Screech going along with it. It lowers your opponent's defense, so you can have a field day when your opponent hurts itself.
28) Defense Curl + Rollout
The only reason that this combination is on here is because of Shuckle. If you use Defense Curl, then Rollout's damage will double. This means that Rollout used by Shuckle will do 1,440 damage instead of 720 damage. This isn't a lot of damage, trust me, since Shuckle's base Attack stat is 10, with 100 and above making a good Physical Sweeper. Of course, this is dangerous, so only someone with godly defenses like Shuckle can pull this off.
29) Mean Look + Spore + Lock-On + Sheer Cold
Since FishMew (Mew with Fissure + Horn Drill + Rest + Sleep Talk) isn't legal in the Third Generation, this is the other cheap OHKO tactic only to be used legally by Smeargle. In my opinion, this doesn't work, because Smeargle has too low defenses. However, if Mean Look is passed to Smeargle, then we have something going on here. Lock-On + Sheer Cold is 100% OHKO, Mean Look prevents your opponent from switching, and Spore prevents your opponent from murdering Smeargle.
30) Hidden Power
This should be a lot higher up the list, but I felt that I've already explained this to you. Hidden Power is used in many ways:
a) To provide a damaging move if the highest damaging move of that type is less than 70 power.
Scizor is a Baton Passer usually, yes, but it still needs a damaging attack. Scizor can use Silver Wind, which is a good attack in because if it raises all of its stats, then that would be a very good thing to Baton Pass! However, some people do no have the patience to breed for Silver Wind, so they might use Hidden Power [Bug], which is a good alternative.
b) To cover weaknesses.
Zapdos is a good Pokémon. It is an extremely good annoying with Substitute + Thunder Wave. However, to Swampert, neither Thunder Wave nor Thunderbolt can work, so Zapdos wants a way to hurt it. Using Hidden Power [Grass] is a good idea.
c) To have a damaging attack.
Believe it or not, but some Pokémon, like Aggron, have a terrible moveset when it comes to giving it damaging moves. For this reason, an Aggron with Choice Band would be likely to have Hidden Power [Rock] or Hidden Power [Steel].
31) Pseudo-Hazing
Like Hidden Power, this section is also last because I've already talked about some of it. I said that Roar and Whirlwind are Pseudo-Hazing moves, and they are. If you force your opponent to switch, then its Status Changes are gone. However, there are more ways. The most common Pseudo-Hazing moves are:
a) Roar and Whirlwind
As I said before, these moves forces switching, so they are the most popular.
b) Status Ailments
Somewhat hinted above, moves such as Sleep Powder, Attract, and Confuse Ray usually make the opponent switch. The reason is, you don't want a Sleeping Pokémon in battle and you also don't want someone with a 25% chance of attacking in battle. Note that Paralysis and Burn also works somewhat, but Tankers and Walls normally stay in.
c) Yawn
Yawn is a move that makes the opponent go to sleep 100% the next move, but not immediately. Your opponent knows that his or her Pokémon will go to sleep, so they usually switch out, giving you a free turn.
d) Leech Seed
Again, no one wants to be Leech Seeded, so they switch out if they think that they are not able to faint the user.
e) Perish Song
Not all uses of Perish Song are Perish Trapping. Your opponent surely doesn't want to be fainted, so they will switch out before the count ends. Perish Song without Mean Look is a hint that you are not wanted.
f) Mind Reader or Lock-On
These moves make the next move have 100% Accuracy, and most Pokémon will be switched out. The reason is because an OHKO move is expected, or something that could be annoying such as Zap Cannon or Dynamicpunch.