https://pokepast.es/53530f563245ba7c
I submit one of the best teams I've ever piloted. It is one of my most favourite teams, and has helped me peak #45 on ladder. (elo 1560+)
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Politoed was chosen as it is the only viable rain setter. I use a standard set with scald toxic encore rest. Encore has been instrumental in helping me deny hazards, lock set up sweepers like manaphy into a move, lock pokemon into recover/roost/soft-boiled like clefable, chansey etc. Would definitely NOT swap it.
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The primary rain abuser. Swift swim helps to raise its speed to astronomical levels. It has a great type combination of water dragon that allows it to switch into some moves as well as have insane offensive output. I've used choice specs and life orb, but specs is the more conventional set. Life orb can be opted for some tournaments/to catch people off guard. I've grown to like life orb.
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This is the mega I have chosen for this rain team. Again, it has swift swim, decent typing, great STABs and a movepool that hits ALMOST everything. However, you must keep in mind ORAS mega mechanics, as its base speed is outsped by some pokemon even in swift swim.
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Okay, I really don't know what to say about this pokemon other than the fact that it is ABSOLUTELY cracked. Hands down, one of the MOST INSTRUMENTAL pokemon in this team. Rain Dance is NECESSARY as this team lacks another rain setter besides politoed. Tail Glow at +6 CAN break past chansey with 2 hits if chansey is a little bit chipped/has no eviolite. Hydration honestly is so underrated, it allows manaphy to act as a status absorber sometimes. Energy ball (for waters) can be opted over ice beam (For dragons).
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This pokemon is the hazard setter of choice. A grass/steel type pokemon that is tanky, 4x weak to fire (which is almost halved due to rain), and weak to fighting ONLY with great resistances goes insane in some MUs tbh. I really like leech seed on this set to gain back health, as it can REALLY help it take some fire type attacks in rain consistently. Twave can be used.
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The last pokemon on this team. This team has no removal, ground immunity, is a bit weak to grass and doesn't have viable recovery options. In other words, if this team goes against hazard stack, it has a shitty MU. Latias solves all of these problems, with the bonus of thunder never missing in rain and HWISH to keep our rain abusers/setter safe.
I really enjoyed this team, I hope you all do too :D
(also, i arrived at the same 6 as ruffles' team in invitationals while building. I don't have his team version, however this is something I made myself. You might find sets a BIT unoptimal, but this team has consistently performed for me. I hope it does for you all too.)
EDIT : preventing people from saying first, by saying it myself :D
EDIT 2: S/O RUFFLESPRO (GOAT) and mixnite (GOAT no.2) for helping me out