Overview
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Ludicolo is the only fully evolved Pokemon with the great offensive and defensive typing of Water / Grass, which makes Ludicolo it a force to be reckoned with when it has rain to play in; add its nifty 4x resistance to Water-type moves into the mix, meaning that opposing Water-types can't abuse the rain that Ludicolo is in, and Ludicolo makes a decent rain abuser, with an excellent Speed stat after the Swift Swim boost. However, the weather nerf hit Ludicolo very hard, although it does enjoy there being no more Drizzle + Swift Swim clause to mess around with its sweeping capabilities. It is weak to Flying- and Bug-type attacks, as well as Poison-type attacks which are gaining popularity due to their effectiveness against Fairy-types. Furthermore, when it Ludicolo is outside of the rain, (add comma) its stats are no better than middling, meaning that it is completely reliant on said weather to succeed in OU. Ludicolo receives stiff competition from Kabutops and Kingdra as rain sweepers in OU, both of which have better overall stats, require less team support, and are less reliant on rain to succeed. However, Ludicolo is in no way a bad Pokemon, as it still has its unique typing and blazing Speed once the rain is up.
Rain Sweeper
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name: Rain Sweeper
move 1: Hydro Pump / Surf
move 2: Giga Drain
move 3: Ice Beam
move 4: Focus Blast
ability: Swift Swim
item: Life Orb
evs: 252 SpA / 4 SpD / 252 Spe
nature: Modest
Moves
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Hydro Pump is a monstrous move when the rain is active, as it scores many OHKOs and 2HKOs on Pokemon which do not resist it, such as Bisharp, Thundurus, and Conkeldurr, easing prediction. However, if you fear the accuracy of the move, you can run Surf, although the power drop is noticable. Giga Drain is the Grass-type STAB of choice for Ludicolo as it hits with decent power, covering the Water-types that like to come in and sponge Ludicolo's hits while also providing healing. Ice Beam is there to hit the Grass- and Dragon-types which resist both of Ludicolo's STAB moves. Finally, Focus Blast is an attractive option for hitting Ferrothorn and Abomasnow, (add comma) the latter of which can clear your rain. However, you Ludicolo should only be using this on a predicted switch-in as these two Pokemon are only 2HKOed by Focus Blast and can both maim Ludicolo back with Knock Off and Blizzard, respectively. If you prefer the ability to set up rain yourself with Ludicolo itself predicting a forced switch, you can run Rain Dance. This also has merit for gaining momentum against opposing weather-changer switch-ins. However, this does leave Ludicolo completely walled by the aformentioned Ferrothorn and Abomasnow despite the momentum gained against the latter; as such, it isn't recommended.
Set Details
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The given EVs are simple: maximize Ludicolo's Speed while providing as much punch as possible. Life Orb is used to aid Ludicolo in this respect as it can boost its power to terrifying levels in the case of Hydro Pump and usable levels for its other moves. A Modest nature has been chosen in order to boost Ludicolo's power further, as Ludicolo will mostly be attacking under rain as it is. Swift Swim is used so that Ludicolo actually has some sweeping capabilities, as its Speed stat is otherwise middling.
Usage Tips
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Due to the weather nerf this generation, Ludicolo now has a limited number of turns in which to use rain, so play Ludicolo with precision (i.e., land all of your predictions: Ludicolo doesn't have enough time to using a resisted move). However, you will find that Ludicolo will still be using Hydro Pump most of the time anyway due to its raw power when under rain. Make sure that the rain is always up when you bring Ludicolo in; if it means sacrificing your Politoed to get the rain up, (add comma) so be it. Refresh the rain as much as possible; also make sure that you remove anything that can prevent Ludicolo from successfully sweeping, such as Talonflame and Ferrothorn.
Team Options
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Politoed, most notably the Damp Rock variant, is an amazing partner for Ludicolo for obvious reasons. Kingdra and Ludicolo share the same set of checks and counters offensively, giving you a backup plan when one of them faints and letting one soften walls for the other to break. Additionally, Ludicolo gets past bulky Water-types for Kingdra, making it easier for Kingdra to sweep when Ludicolo cannot. Rotom-W is capable of dealing with Talonflame effectively, making it a valuable asset on any team that features Ludicolo. Rapid Spin and Defog users, most notably Tentacruel for its ability to absorb Toxic Spikes (space) and Latios due to its nicely buffed-up Surf and Thunder, are able to deal with Sticky Web and Toxic Spikes, both of which plague Ludicolo due to the fact that they limit Ludicolo's its sweeping capabilities and wear it down quickly, respectively. Anything with Heal Bell or Aromatherapy to get rid of status from on Ludicolo, such as Chansey, Blissey, (add comma) or Vaporeon, is an excellent teammate. Finally, Thundurus provides a reliable stop to both Ferrothorn and Talonflame, most notably the former as Ludicolo is immune to Leech Seed and Thundurus is immune to Thunder Wave. Thundurus also has great synergy with Ludicolo with its nicely buffed Thunder.
Other Options
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Ludicolo has a massive movepool to use. However, most of Ludicolo's its other options are either outclassed by the options listed or another Pokemon that can do the job much better. First of all, Ludicolo can run Choice Specs for its ability to ease prediction a little, getting a guaranteed 2HKO on Latios with Hydro Pump. However, aside from the fact that Life Orb Ludicolo 2HKOes Latios with Hydro Pump + Ice Beam anyway, the main issue is that Ludicolo needs the ability to switch moves if it wants to do anything useful, as a Choice Specs set is outclassed by most specially based attackers. Energy Ball could be used over Giga Drain for the extra power output, scoring a guaranteed OHKO on 228 HP Azumarill, and Encore is an option for stopping Pokemon from setting up on Ludicolo once the rain has worn off; however, (add comma) Ludicolo misses the healing that Giga Drain provides, (add comma) while Encore has very limited use and is very situational. Scald can be used over Surf or Hydro Pump for the burn chance, however but it lacks in power compared to said moves, missing out on many KOs even when it does burn. Finally, Ludicolo has access to Rain Dish, which could warrant a tank set with Assault Vest. However, the lack of permanent rain this generation diminishes the usefulness of such a set dramatically, so it is not recommended.
Checks and Counters
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**Super Effective Attacks**: Talonflame doesn't care about Swift Swim due to Gale Wings and can OHKO Ludicolo with Brave Bird 100% of the time, although it can't switch in against you directly, forcing it to come in after a fainted teammate, slow U-turn, Volt Switch or Parting Shot, (add comma) or on a predicted Giga Drain. Mega Venusaur doesn't care about Ice Beam due to Thick Fat and can hit Ludicolo hard back with a STAB Sludge Bomb.
**Weather Control**: Anything that can change the weather from rain is a good counter. Offensively, Mega Charizard Y can outpace Ludicolo in the sun and OHKO with a sun-boosted Fire Blast, (add comma) and Mega Tyranitar who can outpace in sandstorm and OHKO with Stone Edge 100% of the time. Defensively, Abomasnow and its Mega Evolution are by far the kings of the heap, only fearing Focus Blast. Ninetales can change change Ludicolo's weather and outpace it to get off a Will-O-Wisp, with specially bulky variants rarely being 2HKOed.
**Tanks**: (space) Kyurem ad Kyurem-B shrug off everything that Ludicolo can throw at them barring Focus Blast and deal heavy damage back with Draco Meteor or Outrage, (add comma) respectively. Also, Assault Vest Goodra can tank even Ice Beams and threaten back with a Dragon Pulse or the rare Sludge Wave or Sludge Bomb. Mega Venusaur fears nothing that Ludicolo can throw at it and can retaliate with a STAB Sludge Bomb.
**Walls**: (space) Ferrothorn and Mega Venusaur wall Ludicolo to no end and can retalliate back with Knock Off or Sludge Bomb, respectively. Furthermore, any special wall, such as Chansey, Blissey, or Assault Vest Goodra, can tank whatever Ludicolo throws at it and stall out Ludicolo's rain with ease.
**Anti-Speed Tactics**: (space) Trick Room leaves Ludicolo in a predicament as Ludicolo the latter is forced to use the rain to have any sort of offensive presence, and Trick Room just flips this on its head. Ludicolo also hates paralysis, as it which cuts Ludicolo's its Speed stat down to a quarter. This means that common users of Thunder Wave, such as Ferrothorn and Thundurus, are able to cause massive problems for Ludicolo. Finally, Sticky Web, while having less of an effect on Ludicolo than paralysis, is still detrimental for Ludicolo. This makes Galvantula and Smeargle, the most common users of the move, checks to Ludicolo, and to top it all off, (add comma) Galvantula is able to 2HKO Ludicolo with Bug Buzz.
**Wearing-Down Residual Damage**: (space) Toxic and Will-O-Wisp are able to wear Ludicolo down quickly in conjunction with the Life Orb recoil. Toxic Spikes can also get this powerful timer onto Ludicolo by inflicting poison. Finally, the combination of entry hazards and phazers increases the rate at which Ludicolo gets worn down further.