Type synergy is one of the most, if not the most important part of teambuilding in competitive Pokémon, whether it would be offensively or defensively, in both VGC or in Smogon. It's also something that a lot of beginners struggle with, so yeah, let's make a guide.
Typing Synergy (Offensively)
Like with defensive synergy, you can experiment with stuff if you want, but you can also use some of these well-known combinations:
Electric / Ice (BoltBeam)
While the BoltBeam combination is mostly known for being part of a moveset, it's also a good offensive dual type core that can pressure a lot of things since the combination of Electric and Ice attacks are almost un-resisted, since the Grass and Ground types that can wall Electric types are very weak to Ice attacks. A well-known BoltBeam core in Singles is Weavile+Manectric (which I covered in this thread) since they are both very fast and powerful and have nice coverage (Knock Off, Overheat). Definitely one of the most easy to build around, but it's still really effective.
Others things
-Even if you have good synergy, that doesn't mean that your team is invincible; for every team, there will always be a more troublesome Pokémon. After all, nothing is perfect in lifeexcept me.
-If you have trouble finding your team's weaknesses, I HIGHLY recommend using this to help you find your team's weaknesses and resistances. It's always very useful when building a team.
Hope this was helpful!
why am I doing this I don't know what I'm doing help
What is synergy?
Synergy is basically how the Pokémon on a team work together; if we are talking about defensive synergy, that means that the Pokémon on the team are able to cover their respective weaknesses. Defensive is very important on balanced and stall team, and also bulky offense to an extent.
An example of good defensive synergy is this core: Mega-Venusaur / Rotom-W / Heatran
This core is often seen on balanced team in ORAS OU because of they cover each others' weaknesses perfectly, allowing it to check a good portion of the metagame.
Offensive synergy is something really different; it's the ability to beat one Pokémon's check and counters with your other Pokémon. This is very important to have on offense (hyper offense and bulky offense).
One of the best example for offensive synergy in my opinion is this core right here: M-Metagross / Hydreigon
This core (which you can read more about in this thread thanks to @Black117) is often seen in Battle Spot Doubles because of it's decent defensive synergy, but mostly for its excellent offensive synergy: Metagross can remove Fighting and Fairy types that are annoying for Hydreigon while Hydreigon can take care of Ghost types for Metagross.
Synergy is basically how the Pokémon on a team work together; if we are talking about defensive synergy, that means that the Pokémon on the team are able to cover their respective weaknesses. Defensive is very important on balanced and stall team, and also bulky offense to an extent.
An example of good defensive synergy is this core: Mega-Venusaur / Rotom-W / Heatran
This core is often seen on balanced team in ORAS OU because of they cover each others' weaknesses perfectly, allowing it to check a good portion of the metagame.
Offensive synergy is something really different; it's the ability to beat one Pokémon's check and counters with your other Pokémon. This is very important to have on offense (hyper offense and bulky offense).
One of the best example for offensive synergy in my opinion is this core right here: M-Metagross / Hydreigon
This core (which you can read more about in this thread thanks to @Black117) is often seen in Battle Spot Doubles because of it's decent defensive synergy, but mostly for its excellent offensive synergy: Metagross can remove Fighting and Fairy types that are annoying for Hydreigon while Hydreigon can take care of Ghost types for Metagross.
Typing Synergy (Defensively)
When you are looking for defensive synergy on your team, it's most likely because you want a defensive backbone for your team. Obviously, to find a good core, you can play around with Pokémon until you find something sweet, but if you are looking to make a good defensive cores, try one of these:
Fire / Water / Grass (FWG)
Fire / Water / Grass is one of the most effective three-types core in a lot of metagames, like Smogon tiers and VGC. Water types can sponge attacks from Ice, Fire, and Water types that threaten Grass and Fire Types. They also check Steel types that Grass types can't hit for much. Bulky Waters are also bulky enough to act as a check to Ground an Rock types that are annoying for Fire types. Meanwhile, Grass types take care of Ground, Electric, Water (and check Rock types) to help his Fire and Water type teammates. Finally, Fire types can take care of Bug, Grass, Ice and Steel for Grass types. Also, since all of these are quite common typings, you can quite easily find stuff to furthermore benefit the teams: you have access to Stealth Rock, Rapid Spin, Speed Control with Icy Wind and Thunder Wave, Tailwind and Trick Room setters, and much more with all the choice you got.
Dragon / Steel / Fairy (DSF)
Dragon / Steel / Fairy is one of the most, if not the most effective defensive core type in Singles and it's also pretty good in Doubles. Dragon types have always been very good both offensively and defensively, Kalos gave us a lot of great Fairy types with good bulk, and Steel types have always been known for their defenses. The Fairy type is able to deal with Fighting attacks that would annoy the Steel type, and the Steel type walls Poison and Steel types. The Dragon type benefits from all of the other two's resistances while providing useful resistances to Grass, Water, Fire and Electric. Like with the FWG cores, they just check each others' weaknesses very well and are great to have on every team.
When you are looking for defensive synergy on your team, it's most likely because you want a defensive backbone for your team. Obviously, to find a good core, you can play around with Pokémon until you find something sweet, but if you are looking to make a good defensive cores, try one of these:
Fire / Water / Grass (FWG)
Fire / Water / Grass is one of the most effective three-types core in a lot of metagames, like Smogon tiers and VGC. Water types can sponge attacks from Ice, Fire, and Water types that threaten Grass and Fire Types. They also check Steel types that Grass types can't hit for much. Bulky Waters are also bulky enough to act as a check to Ground an Rock types that are annoying for Fire types. Meanwhile, Grass types take care of Ground, Electric, Water (and check Rock types) to help his Fire and Water type teammates. Finally, Fire types can take care of Bug, Grass, Ice and Steel for Grass types. Also, since all of these are quite common typings, you can quite easily find stuff to furthermore benefit the teams: you have access to Stealth Rock, Rapid Spin, Speed Control with Icy Wind and Thunder Wave, Tailwind and Trick Room setters, and much more with all the choice you got.
Dragon / Steel / Fairy (DSF)
Dragon / Steel / Fairy is one of the most, if not the most effective defensive core type in Singles and it's also pretty good in Doubles. Dragon types have always been very good both offensively and defensively, Kalos gave us a lot of great Fairy types with good bulk, and Steel types have always been known for their defenses. The Fairy type is able to deal with Fighting attacks that would annoy the Steel type, and the Steel type walls Poison and Steel types. The Dragon type benefits from all of the other two's resistances while providing useful resistances to Grass, Water, Fire and Electric. Like with the FWG cores, they just check each others' weaknesses very well and are great to have on every team.
Typing Synergy (Offensively)
Like with defensive synergy, you can experiment with stuff if you want, but you can also use some of these well-known combinations:
Electric / Ice (BoltBeam)
While the BoltBeam combination is mostly known for being part of a moveset, it's also a good offensive dual type core that can pressure a lot of things since the combination of Electric and Ice attacks are almost un-resisted, since the Grass and Ground types that can wall Electric types are very weak to Ice attacks. A well-known BoltBeam core in Singles is Weavile+Manectric (which I covered in this thread) since they are both very fast and powerful and have nice coverage (Knock Off, Overheat). Definitely one of the most easy to build around, but it's still really effective.
Dark / Fighting / Psychic (DFP)
This is one of the best offensive type core in the game at the moment, in both Singles and Doubles. This is very common, and you might see some two-types core based on this like Fighting/Dark (like the Blaziken/Bisharp core in this thread) or Dark/Psychic like the Hydreigon/Metagross core I talked about earlier. It is just so efficient because it is so easy to use: the Dark type takes care of the Psychic types that are annoying for the Fighting type, the Psychic type takes care of the Fighting type that would be threatening to the Dark type and, finally, the Fighting type removes opposing Dark types to help the Psychic type. A very good example for this kind of core in ORAS OU is Keldeo/Bisharp/Latios; with Keldeo, you can bait in Lati@s and switch aggressively to your Bisharp, which should have Pursuit to trap it. Then, Keldeo lost one of his best checks and it suddenly becomes an even bigger threat. Meanwhile, Latios deals with the Fighting types that would be troublesome for the two others.
This is one of the best offensive type core in the game at the moment, in both Singles and Doubles. This is very common, and you might see some two-types core based on this like Fighting/Dark (like the Blaziken/Bisharp core in this thread) or Dark/Psychic like the Hydreigon/Metagross core I talked about earlier. It is just so efficient because it is so easy to use: the Dark type takes care of the Psychic types that are annoying for the Fighting type, the Psychic type takes care of the Fighting type that would be threatening to the Dark type and, finally, the Fighting type removes opposing Dark types to help the Psychic type. A very good example for this kind of core in ORAS OU is Keldeo/Bisharp/Latios; with Keldeo, you can bait in Lati@s and switch aggressively to your Bisharp, which should have Pursuit to trap it. Then, Keldeo lost one of his best checks and it suddenly becomes an even bigger threat. Meanwhile, Latios deals with the Fighting types that would be troublesome for the two others.
Others things
-Even if you have good synergy, that doesn't mean that your team is invincible; for every team, there will always be a more troublesome Pokémon. After all, nothing is perfect in life
-If you have trouble finding your team's weaknesses, I HIGHLY recommend using this to help you find your team's weaknesses and resistances. It's always very useful when building a team.
Hope this was helpful!