This is my first contribution towards these things as I am a fan of these and I have been using this set a few times. Hope this works for you guys!
Druddigon @ Custap Berry/Lum Berry
Trait: Mold Breaker
EVs: 72 HP / 236 Atk / 200 SDef
Adamant Nature (+Atk, -SAtk)
- Superpower / Fire Punch
- Earthquake
- Sucker Punch
- Taunt / Stealth Rock
Say hello to one of Politoed's best friend. This set seems like it might be outclassed by Dragonite as he does pose a better attack stat and a better survivability or Haxorus which has most of the available moves in this set but what Dragonite and Haxorus don't have is Fire Punch, Sucker Punch, and the ability to ignore Magic Bounce and setup Stealth Rocks or Taunt the somewhat common Dual Screen Espeon. This leads the door to many possibilities leading it to score surprising 2HKOs and some OHKOs. The first move is a crucial decision as both Superpower and Fire Punch open doors to which type of pokemon Druddigon want's to defeat. It can choose to go with Superpower and KO Tyranitar for setting up it's precious Sand or hault Ferrothorn or Forretress from setting up two layers of Hazards and to add onto coverage for other grass types. Earthquake and Sucker Punch are mandatory as they are both needed to distance itself from Anti-Lead Dragonite and to surprise attack against Espeon, Starmie, and other Psychic Pokemon. The fourth tier is up to the user's preference. If you choose Superpower, Taunt would be your best option as it haults Skarmory and Chansey from performing status or hazards. Stealth Rocks would be in favor if you choose Fire Punch as Druddigon is one of the safest pokemon to setup with Stealth Rocks as Magic Bounce is canceled by Mold Breaker. As for the OHKO's and 2HKO's this surprise dragon can pull, here's some numbers against pokemon that are common leads and some pokemon that Druddigon can threaten or check.
OHKOs
236+ Atk Druddigon Superpower vs. 252 HP / 0 Def Tyranitar: 496-584 (122.77 - 144.55%) -- guaranteed OHKO [Support Tyranitar]
236+ Atk Druddigon Earthquake vs. 4 HP / 0 Def Infernape: 296-350 (100.68 - 119.04%) -- guaranteed OHKO [Choice Banded]
236+ Atk Druddigon Earthquake vs. 0 HP / 0 Def Ninetales: 284-336 (98.95 - 117.07%) -- 93.75% chance to OHKO [Special Attacker] (OHKO After Stealth Rocks)
236+ Atk Druddigon Fire Punch vs. 0 HP / 0 Def Scizor: 340-400 (120.99 - 142.34%) -- guaranteed OHKO [Choice Scarf]
236+ Atk Druddigon Fire Punch vs. 252 HP / 172 Def Abomasnow: 348-412 (90.62 - 107.29%) -- 43.75% chance to OHKO [SubSeed] (OHKO After Stealth Rocks)
2HKO
236+ Atk Druddigon Fire Punch vs. 252 HP / 88+ Def Ferrothorn: 224-268 (63.63 - 76.13%) -- guaranteed 2HKO [OU Standard]
236+ Atk Druddigon Earthquake vs. 252 HP / 0 Def Jirachi: 224-264 (55.44 - 65.34%) -- guaranteed 2HKO [Specially Defensive]
236+ Atk Druddigon Sucker Punch vs. 252 HP / 0 Def Starmie: 206-244 (63.58 - 75.3%) -- guaranteed 2HKO [Defensive Rapid Spin]
236+ Atk Druddigon Sucker Punch vs. 252 HP / 4 Def Espeon: 270-318 (80.83 - 95.2%) -- guaranteed 2HKO [Dual Screen]
And some honorable mentions would be with Fire Punch can threaten any standard set of Breloom, Forretress and Heracross with a 2HKO
outside of rain, Earthquake onto the OU sets of Jolteon, Lucario, Toxicroak, Heatran, and Magnezone will OHKO, Sucker Punch can swiftly stop Gengar's disable and Offensive 3 Attacks sets, and Superpower onto Weavile, Mixed Attacker Hydreigon, and some of the Cholorophyll Sweeps such as Sawsbuck and Shifty will be knocked out in a OHKO. This set seems very frightening to a lot of pokemon onto the metagame as this scares away a lot of pokemon out of the field as your surprise your foe with a OHKO and you can safely bring your Politoed in to win the weather wars. The only problem that Druddigon has in stopping weather setup pokemon is Hippowdon. But the good news is that most sets run him with the inclusion of Whirlwind and Stealth Rocks so you can at least cripple the Hippo before sending out Politoed or another powerful pokemon to force or kill off Hippowdon to increase your odds at winning the weather wars.
The EV's are set to make sure that Druddigon lives off Ice Beams, and a few Blizzards from various pokemon such as Choice Scarfed Abomasnow, and Offensive Starmie. The Offensive stats are to make sure that the list of OHKO's and 2HKO's listed above are made possible. Jolly nature seems like a good idea but this set is still completely walled up by Jellicent and you would be losing out on some very important KO's.
Now, going back to the list of pokemon this thing OHKOs and 2HKOs, you'd think this pokemon would be hard to destroy without getting some damage back. Druddigon isn't perfect, as he can be wall'd by Jellicent, most Water types packing Ice Beam such as Vaporeon, every Dragon type that isn't Druddigon, and Skarmory. However, Skarmory must be wary of Taunt so it'll only be able to setup one layer of hazards. The thing with this set isn't to counter with those pokemon rather it be more of a wall or counter. It's to get a lead on the opponent and to do as much damage and run out to increase your odds to permanently bring up Drizzle onto your team. A few partners that can help KO what Druddigon can't is Jolteon, Thundurus-T, or Air Balloon Magnezone. The three can all dish out massive amounts of damage onto water-types that wall Druddigon completely while also including a status that can cripple Chansey and Blissey out into another pokemon. Another partner is ironically, a pokemon that can 2HKO Druddigon itself! Starmie with it's BoltBeam combo can scare a lot of Water-types and Dragon-types that aren't Choiced into sheer terror. Also, it can spin off any Stealth Rocks or Spikes that might have landed during the course of Druddigon being alive for a short or long period of time.
[This set took me a few hours of analyzing and discovering but I hope this set works and I hope that it can work out for your team as well. If there is any improvements I can make to it, let me now and thanks for reading! ^^]