Gyarados is a potent sweeper thanks to its unique offensive Water and Flying typing. However, it still needs the proper support to succeed in the current metagame. Your team does a decent job at supporting it, but I believe it can be tweaked to be more effective.
The primary weakness that I see with your team is
no Ground-type. Due to Gyarados's 4x Electric weakness, it is crucial that you have a Ground- type on your team, otherwise Pokemon like Tapu Koko will easily pressure your entire team and prevent Gyarados from accomplishing its job.
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Next, let's analyze some specific
threats:
Electric-types such as
Tapu Koko and
Zapdos can be really annoying due to your team containing no Ground-type. Tapu Koko gets to fire off free Thunderbolts and pivot out against Bulu, your only 'switch-in'. Zapdos also gets to just sit there and fire off Discharges and hope to para your entire team.
Again, because of no Ground-types,
Tyranitar gets to fire off a powerful Stone Edge every single time and your team's best resist is Kartana - everything else either gets OHKOd or 2HKOd.
Flying-types can get a bit annoying since your only resist is Heatran, which isn't hard to wear down.
Hawlucha in particular can set up against the likes of Tapu Bulu and proceed to sweep your team with prior damage on Clefable.
Psychic-types such as
Mega Alakazam and
Tapu Lele can cause problems due to Heatran being worn down very easily. Tapu Bulu's current spread doesn't let it reliably beat Lele atm, and Mega Zam can even abuse Heatran by tracing its Flash Fire and outspeeding everything bar Kartana.
With Heatran gone,
Mega Scizor proceeds to very easily set up against Clefable and wall the rest of your team.
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These are the
changes that I believe will make your team better:
>
Your main reasoning for having Torn-T on the team was to deal with Kartana, Lando-T, and pressure grasses, all of which
Zapdos can do. Zapdos also has the additional benefit of helping your team with Flying-types such as Hawlucha and Torn-T, as well as some other annoying Pokemon like Mega Scizor and Kartana more reliably than Torn-T. You miss out on Hurricane, but the chance of spreading paralysis due to Discharge can help Gyarados later on in the game.
>
This was a hard change to make, but I think that your team gains more than it loses from making it.
Zygarde provides your team with a valuable Ground resist that it currently lacks while maintaining offensive presence. Thanks to its good bulk, it can always beat Tapu Koko 1v1 (especially because Specs isn't common anymore). You do lose out on passing healing to Tapu Bulu and Heatran, but you gain the ability to pressure Steel-types that would annoy Kartana, Tapu Bulu, and most importantly, Gyarados. On top of this, Zygarde brings priority through espeed to help pick off weaken foes. Adding Zygarde allows you to exert even more offensive pressure on your opponent, as Grass spam + CB Zyg + Z-Gyara makes your team very scary, and leaves it better off vs Electric- and Rock- types.
SpD, Rocks > WoW, Toxic > Taunt (optional)
Because Heatran is the only bulky Steel-type that your team contains, I think it'd be better to give it some
SpD investment. This allows it to take on the likes of Mega Alakazam and Tapu Lele a bit easier since it's the primary switch-in against those. After that, I would run Stealth Rock > WoW because I replaced Clefable. An alternative that you could also try is Toxic > Taunt; it makes you weaker against CM users like Clefable and Reuniclus, but it lets you wear down any Pokemon without Magic Guard (Mega Zam, Ash-Gren, etc) to facilitate Gyarados' shot at sweeping.
--> new EV spread
Minor change, but I would personally alter
Bulu's spread to handle PsySpam and Ash-Greninja better. This also means that you can have another soft check for Lele instead of bringing in Heatran every time.
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In conclusion, I think that this final team does a more consistent job at wearing down the opponent and ultimately allowing one of your sweepers to clean. Replacing Clefable means that your team becomes a bit weaker to
, but Tapu Bulu + Kartana can usually handle it.
is a threat because you utilize Tapu Bulu to handle it, but luckily it only really comes in freely against Heatran.
can be annoying if you let your offensive Pokemon get weakened. Lastly, losing Clefable also means that
becomes scarier, but like Ash-Greninja, it doesn't get to come in often (not like Clefable always beats it, either). Enjoy!