Please note that this is not a tiering discussion. A thread on Swampert emerged on here a few days ago but it was deleted, and I don't know why. I thought I'd try my hand at writing a new one, but if there's a problem with Swampert threads please let me know so that I can delete it ASAP.
Swampert - The Mud Fish Pokemon
Water/Ground
Base Stats: 100/110/90/85/90/60
Abilities

Water/Ground
Base Stats: 100/110/90/85/90/60
Torrent: When Swampert's HP reaches 1/3 of its maximum amount, its Water-type moves get a power boost of 50%.
Damp (Dream World Exclusive): The moves Explosion and Self Destruct cannot be used whilst Swampert is in play.
0x Immunities: Electric
0.25x Resistances: None
0.5x Resistances: Fire, Rock, Poison, Steel
1x Neutralities: Normal, Water, Ice, Fighting, Ground, Flying, Psychic, Bug, Ghost, Dragon, Dark
2x Weaknesses: None
4x Weaknesses: Grass
Swampert has been a big player in competitive Pokemon in every generation it has been available in. Generation III saw Swampert take the role of one of the best Bulky Waters available. Though it faced stiff competition from the likes of Milotic and, to a lesser extent, Ludicolo, Swampert was able to carve out a niche for itself using its high Attack stat, excellent mixed defences and fantastic defensive typing. Nothing really changed for Swampert in Generation IV but the game around it had changed a lot; attacks were hitting harder than ever, there was a Dragon-type on every team and the metagame was centered around the new entry hazard Stealth Rock. Fortunately for Swampert its defenses were more than sufficient to take quite a beating from even the hardest hitters, it was one of the best physical Dragon-type counters around and it quickly shone as one of the very best users of Stealth Rock. Swampert was one of the few Gen IV Pokemon to remain a consistent Top 20 choice throughout the years alongside giants like Gengar, Starmie and Gyarados. By the end of Generation IV, Swampert had become a Top 5 lead due to its staying power and good match ups with other leads, not to mention how good it was at setting up SR. With the ability to reliably counter massive threats like Heatran, Metagross and Zapdos, Swampert was probably the top Bulky Water in Gen IV.
In Generation V, it doesn't look like much is going to change for Swampert. Stealth Rock is a bit more limited now and players will need to rely mostly on Gen IV Pokemon to set it up; as one of the best Gen IV Stealth Rock users, Swampert's services will likely be called upon once again. Many of the most threating new sweepers like Doryuzuu, Randorosu and Ononokusu are physically based and seem very scary, but Swampert can answer all of them with its STAB Earthquake and decently powered Ice Beam. And whilst it can be said that Swampert didn't gain much from the new games, it really doesn't need anything more than what it already has. With its excellent typing, solid defences and new toys to play with in Boiling Water and Damp, expect Swampert to be a great defensive force in the BW metagame.
Swampert's Learnset
Notable moves are bolded.
New moves are italicised.
Notable new moves are bolded and italicised, and will be explained at the bottom of each codeset.
Level-Up Moves
Code:
Level 1: Tackle
Level 1: Growl
Level 1: Mud-slap
Level 1: Water Gun
Level 6: Mud-Slap
Level 10: Water Gun
Level 15: Bide
Level 16: Mud Shot
Level 20: Foresight
Level 25: Mud Bomb
Level 31: Take Down
Level 39: Muddy Water
[B]Level 46: Protect
Level 52: Earthquake
Level 61: Endeavor
Level 69: Hammer Arm[/B]
Level 24 (As Mudkip): Mud Sport
Level 33 (As Mudkip): Whirlpool
[B]Level 42 (As Mudkip): Hydro Pump[/B]
TM Moves
Code:
[B]TM05: Roar
TM06: Toxic[/B]
TM10: Hidden Power
[B]TM13: Ice Beam[/B]
TM14: Blizzard
TM15: Hyper Beam
[B]TM17: Protect[/B]
TM18: Rain Dance
TM21: Frustration
[B]TM26: Earthquake[/B]
TM27: Return
TM28: Dig
TM31: Brick Break
TM32: Double Team
[I]TM34: Sludge Wave[/I]
TM39: Rock Tomb
TM42: Facade
[B]TM44: Rest[/B]
TM45: Attract
[I]TM48: Sing A Round
TM49: Echo Voice[/I]
TM52: Focus Blast
[I][B]TM55: Boiling Water[/B][/I]
TM56: Fling
TM68: Giga Impact
[B]TM71: Stone Edge[/B]
[I]TM78: Level Ground[/I] [B]TM80: Rock Slide[/B]
TM87: Swagger
TM90: Substitute
TM94: Rock Smash
[B]HM03: Surf[/B]
HM04: Strength
[B]HM05: Waterfall[/B]
HM06: Dive
Egg Moves
Code:
Gust
[B]Refresh[/B]
Uproar
Curse
Stomp
Ice Ball
[B]Mirror Coat
Counter[/B]
Ancientpower
Whirlpool
Bite
Double-edge
Mud Bomb
[B]Yawn[/B]
Sludge
[B]Avalanche[/B]
[I][B]Wide Guard[/B][/I]
Gen IV Exclusive TM Moves
Code:
TM01: Focus Punch
TM03: Water Pulse
TM07: Hail
TM23: Iron Tail
TM43: Secret Power
[B]TM58: Endure[/B]
[B]TM72: Avalanche
TM76: Stealth Rock[/B]
TM78: Captivate
TM82: Sleep Talk
TM83: Natural Gift
HM08: Rock Climb
Gen IV Exclusive Move Tutor Moves
Code:
[B]Ice Punch[/B]
Icy Wind
Snore
Aqua Tail
Earth Power
Outrage
Rollout
Superpower
Low Kick
Headbutt
Gen III Exclusive Move Tutor Moves
Code:
Mega Punch
Mega Kick
[B]Body Slam[/B]
Seismic Toss
Mimic
DynamicPunch
Defence Curl
Boiling Water: Water-type Special move, 80 BP/100 Acc/15 PP. Has a 30% chance of burning the opponent.
Wide Guard: Rock-type Status move, -- BP/-- Acc/10 PP. Protects the user from attacks, and also protects teammates in Double or Triple battles.
Swampert also learns Hydro Cannon and Water Oath from Gen V Move Tutors, but neither of these are noteworthy.
Swampert's Pros and Cons
Pros:
- Brilliant defensive typing. Water is a great typing anyway with four key resistances and only a couple of weaknesses, but Water/Ground is arguably even better. Trading a Water and Ice resistance for a Rock and Poison resistance and an Electric immunity is a great deal, and Swampert only has one weakness as a result. Fortunately, this weakness is to Grass-type moves and not only are Grass-type moves uncommon, but it's easy to know when they're coming since they're only used as STABs (or on a couple of specific sweepers). Swampert needs to be more wary of surprise Hidden Power Grass on stuff like Magnezone, Heatran and Zapdos, all of which often run HP Grass purely for Swampert.
- Great defences. 100/90/90 defences might look underwhelming, but Swampert has key resistances to the main STABs of a lot of threatening Pokemon, most notably Rock, Fire and Electric. This means it can take quite a beating before going down, and Wish support isn't even necessary.
- Good movepool. Between its Ground, Water and Ice attacks, Swampert can hit pretty much any opponent with a decently powered attack. It also gets some great support options like Roar and Yawn, a great setup move in Curse, and of course the infamous Stealth Rock.
- Great new ability. The only thing stopping Swampert from becoming a 100% Heatran/Non-Mixed Metagross counter was the fact that both of them could just blow up on him and end his life. Damp stops this from happening and can also stop Randorosu from blowing up on Swampert, thus making Swampert a better counter to these Pokemon in Gen V. Unfortunately, Damp is incompatible with Stealth Rock. However, Explosion and Self Destruct no longer halve the Defence stat of the targetted Pokemon (giving them effective Base Powers of 500 and 400 respectively) which means Damp might not be all that necessary on Swampert after all, since Heatran and probably Metagross will be unable to OHKO it with Explosion. Still, if your Swampert isn't using Stealth Rock, Damp is a great ability choice on a defensive set.
- Theoretically able to counter some huge new BW threats. As I mentioned earlier, many of the new BW threats are either part Ground or part Dragon. Swampert has the moves to deal with pretty much any Ground or Dragon type besides Gen IV Ubers and argubaly Sazando (Ice Beam doesn't quite hit hard enough), so expect it to be a staple on defensive and balanced teams alike. It also has the means to deal with the new-and-improved Blaziken, as well as most Shanderaa.
- Immunity to Sandstorm and resistance to Stealth Rock. These attributes are hardly rare, but they're always nice to have.
Cons:
- Has a crippling 4x weakness. Grass is an uncommon attacking type - it is resisted by loads of common Pokemon and it only hits three types for Super Effective damage. However, Swampert is a massive defensive threat for many sweepers and they often run Hidden Power Grass to tackle him. The long and the short of it is that if you get hit by a Grass-type move, you're dead.
- Fairly low damage output. 110/85 attacking stats are pretty good for a tank, but the standard Swampert runs very few Attack/Special Attack EVs and thus deals very little damage to things. If Swampert can't hit the opposing Pokemon for Super Effective damage, it's probably not gonna be doing much to it.
- No reliable recovery move (thanks to Forte for reminding me of this). Gastrodon, Milotic, Burunkeru and Quagsire get Recover, Vaporeon gets Wish, Swampert gets... oh. Yeah, Swampert can't really heal itself outside of Rest, which now forces you to sleep for 3 turns and is even more useless in the 5th generation. At least it cures you of status... Still, Swampert often doesn't stick around for as long as you'd hope since he can't heal himself outside of Leftovers.
Moveset Ideas
Mixpert's New Groove
Swampert@Leftovers/Shed Shell
Torrent/Damp
Relaxed Nature
EVs: 252 HP/252 Def/4 SpA
~ Earthquake
~ Ice Beam
~ Stealth Rock/Boiling Water
~ Boiling Water/Roar/Yawn/Wide Guard or Protect/Stone Edge
This has been the bread and butter Swampert set for two generations of Pokemon and there's no reason for it to change now. Earthquake is a powerful STAB move which hits everything that doesn't resist it hard, whilst Ice Beam smacks Flying-types with a Super Effective move and makes Dragon-types cry and Stealth Rock is an incredibly good entry hazard. The last slot has several viable options. Boiling Water is a great new move which trades a bit of Surf's power for a 30% burn chance - a worthy trade-off if you ask me. A burn lessens the amount that Swampert takes from physical attacks even more and hence makes it a better tank. I expect its main use will be against Gyarados (should Gyarados even stay OU) but other Swampert switch-ins will hate to be burned, like Life Orb Latias and MixMence who think they're clever getting in on Earthquake, or even Shed Shell Nattorei, which is pretty much a 100% Swampert counter. Boiling Water should also do quite a number to Skarmory and might allow Swampert to eventually beat the steel bird. Roar is always good for phazing and Yawn accomplishes the same thing really, plus putting something to sleep is always nice; Swampert is bulky enough to pull phazing off quite effectively. Protect was great on Gen IV Mixpert as a scout and it's just as good here, but Wide Guard gets a mention for Double/Triple battles since it protects the whole team (remember that Wide Guard is incompatible with Stealth Rock). Finally, Stone Edge hits Gyarados hard as well as hitting sweeping Zapdos harder than Ice Beam, though Boiling Water is probably better against Gyarados for the burn chance. Hydro Pump and Toxic are also options for the last slot, but they were inferior in Gen IV and probably won't see much Gen V use either.
The EVs are standard for a defensive wall, with a Relaxed nature so as not to ruin Ice Beam and Boiling Water. In late Gen 4 Swampert started to run a few Special Defence EVs to take Heatran's Fire Blasts and stuff, but it's gonna need all the Defence it can get to stand up to repeated beatings from Randorosu and Doryuuzu. The remaining EVs are chucked into Special Attack to give Ice Beam that little bit more bite against Dragon-types. Leftovers are easily the best item for Swampert and you probably think I'm mad suggesting Shed Shell, but it could come in handy in case Shanderaa and Goth Psychic start to trap weakened Swamperts a lot (Shanderaa in particular, since it's gonna be on every team). Swampert's moveset should decide his ability - use Torrent with SR and Damp without SR. Boiling Water is slashed with Stealth Rock in case you have another Stealth Rock user and want Swampert to be a pure tank; if you're using SR you have two free moveslots and there's no excuse not to use Boiling Water.
Curses!
Swampert@Leftovers
Torrent
Careful Nature
EVs: 252 HP/40 Def/216 SpD
~ Curse
~ Rest
~ Earthquake/Waterfall
~ Sleep Talk
Pretty much ripped this from the analysis site, it might work in BW. Curse because... it's a Curse set, and Rest for healing. Rest makes you sleep for three turns now so you really can't afford to not use Sleep Talk, hence why it isn't slashed with anything. Earthquake vs Waterfall is sort of a pick-your-poison deal; Earthquake is more powerful, but Waterfall is more reliable and nothing is immune to it barring Water Absorbers. 252 HP EVs give a lot of bulk, whilst 216 SpD EVs let Swampert hit the last bonus point. The rest of the EVs are dumped into Defence. Unfortunately, Damp is incompatible with Sleep Talk, so you're stuck with Torrent.
Counters
Non BW Pokemon: Swampert is hard to take down, but Grass-types have no trouble with it. Celebi and Shaymin take lolworthy damage from Ice Beam and can OHKO it with STAB Grass-type moves. The Rotom forms still have an easy time against Swampert, barring Rotom-H since Swampert resists both of its STABs and hits it for Super Effective damage with Boiling Water. Rotom-C and Rotom-W will easily beat Swampert though, with Leaf Storm and Hydro Pump respectively. Defensive Zapdos (basically, any Zapdos which invests in HP) with HP Grass can beat Swampert as well, as can Gyarados which can use Swampert as setup fodder (though Gyarados must be extremely careful of Boiling Water). Ironically, although Swampert was the most popular Bulky Water in Gen IV it has trouble beating other Bulky Waters; Vaporeon, Suicune and Milotic can all beat Swampert one on one. Finally, the Lati twins don't really like Ice Beam and won't be mad on Boiling Water burns either, but they can take most of Swampert's attacks and OHKO it with Specs Draco Meteor.
BW Pokemon (be warned - these are theoretical!): Nattorei (the new Grass/Steel Forretress) was made to beat Swampert! It resists Water-type moves and has massive defensive stats to take Earthquake and Ice Beam with, and it can OHKO Swampert with STAB Power Whip. The new jellyfish Burunkeru should be able to beat Swampert too, with Water Absorb making Boiling Water useless. The fearsome Shanderaa cannot switch into Swampert's STABs, but once it's in it can trap a weakened Swampert and kill it with Shadow Ball. Sazando (Dragon/Dark Hydra) also fares well against Swampert, as it doesn't take much damage from Ice Beam and can put the hurt on Swampert with a more powerful Draco Meteor than Latias.
So, what do we think of Swampert this generation? Will it be just as awesome a defensive pivot as ever, or will the incredibly high powered new Pokemon prove to be too much for it? Discuss!