Since this thread has been lacking activity lately, I'll nominate something.
Let's take a look at what bothers our Meloetta set (Relic Song / Close Combat / Thunder / Hidden Power Ice @ Expert Belt):
Now what can deal with these Pokemon? I think for the nominations now, we either need Pokemon that can switch into these Pokemon easily and force them out, or lure them in and take them out.
I have several nominations. The first is the following:
Latios @ Choice Specs
EVs: 4 HP / 252 SAtk / 252 Spd
Timid Nature (+Spd, -Atk)
- Draco Meteor
- Dragon Pulse
Specs Latios is one of the best Pokemon on rain offense in my opinion. Draco Meteor and Surf provide perfect coverage, and both are 1.5x boosted, either by STAB or by rain. Draco Meteor can rip holes in teams, while Surf takes care of resists such as Genesect, KOing with the rain boost. Lategame, either Dragon Pulse or Surf can take out the remainings of a team, depending on the situation. Both have a solid 90 base power, perfect accuracy, and good neutral coverage. Trick is in the last slot, as Latios can lure in several threatening Pokemon for Meloetta and Trick them, such as Jirachi and Metagross. That way, they are crippled and easily set up on. Other than that, rain-boosted Surf will leave a dent in them, as Metagross takes about 70 - 80%, while Jirachi takes about 45%. Reuniclus and Amoonguss are outsped, walled (though beware of double powder from the latter), and KOed with Draco Meteor or crippled with Trick. Latias can be taken down if Latios wins the speedtie, or if Latias is unboosted in which case Dragon Pulse only does about 70%.
Jynx @ Leftovers
Trait: Dry Skin
EVs: 8 HP / 248 SAtk / 252 Spd
Timid Nature (+Spd, -Atk)
- Nasty Plot
- Ice Beam
- Lovely Kiss
Jynx is a cool and underrated Pokemon in rain offense teams. Dry Skin is a great ability, and with it and Leftovers Jynx recovers 18.75% of its health every turn. This means that it only loses 6.25% when using Substitute, and it can make 12 Substitutes from full health. Lovely Kiss and Nasty Plot are great moves, with the former being able to completely cripple an opposing Pokemon, making it unable to do anything unless it stays in for several turns in a row. The latter doubles Jynx's already respectable Special Attack stat, and if Jynx has a Substitute up as well as a Nasty Plot, Ice Beam is gonna hurt. This can be accomplished by playing Lovely Kiss well, and preferably bringing Jynx in on a wall that can't hurt it, or a Choiced Water- or Ice-type attack from the likes of Politoed. Ice is a good mono-attacking type, and really only Heatran and Tyranitar easily stop this set. Now, what does this Pokemon do for the team besides being generally awesome? First off, Reuniclus, Amoonguss, and Latias are taken care of by this Pokemon. Reuniclus only 3HKOes Jynx with Focus Blast, so Jynx can Nasty Plot up and do 90% to Reuniclus with Ice Beam, KOing with a bit of prior damage, or putting it to sleep with Lovely Kiss. Amoonguss does about 30% with Giga Drain, which after recovering is only about 10 - 15% a turn. Substitute blocks Spore, and Ice Beam KOes. Latias doesn't 2HKO with Dragon Pulse, and +2 Ice Beam always OHKOes Latias, or Jynx can just put it to sleep with Lovely Kiss. Jirachi, Volcarona, and Metagross on the other hand all like to switch in on Jynx, but Lovely Kiss will cripple them, leaving them easier to handle for Meloetta.