~ Curse
~ Earthquake
~ Ice Beam / Rock Slide
~ Surf / Hydro Pump / Rest
252 HP / 136 Def / 120 SpA
This Pokémon is one of the most commonly used Water-types out there, but it has some major problems. First of all, Ice Beam doesn't really hurt Skarmory or Weezing enough to deter them away. Rock Slide does absolutely nothing to them, and Surf leaves you helpless against Salamence. It's up to you to decide which move to give it to best suit your team. Regardless, Ludicolo and Celebi will own you no matter what set you have. It makes a really nice Blissey counter and you can get it in easily against the majority of things, such as Salamence, Tyranitar, and Metagross.
Like Snorlax, this Swampert is good late in the battle when the opponent's main counters have been weakened or KOed so it that can use Curse. If left as the last Pokémon, it won't have to fear enemies who use Roar or Whirlwind as their means of countering stat uppers. If you want to employ such a strategy, Rest is a good option to keep on going.
~ Hydro Pump / Surf
~ Ice Beam
~ Earthquake
~ Protect / Rest / Roar
252 HP / 136 Def / 120 SpA
Notorious at forcing switches, but doesn't really cause much damage to anything. If the opponent switches out due to fear of Earthquake, you can use Ice Beam on a predicted Grass type or a Water attack for the likes of Gengar and Skarmory. Hydro Pump is sometimes used since it is powerful enough to do major damage against most Gengar, but Surf is always an option for those who prefer better accuracy and more PP. Protect is there to get you Leftovers recovery (which will happen even if Sand Stream is up), and lets you scout Choice Banders as well as Explosion, especially handy for Metagross. Usually it suffices as a recovery option, as a Resting Swampert tends to lose against Dragon Dancers if it's not healed by Aromatherapy or Heal Bell. Roar can take advantage of Swampert's ability to force switches by Roaring them as they switch, causing the opponent to take two layers of Spikes damage. However, you'll really want to use this with Wish, as without Protect or Rest to heal it up, Tyranitar and Salamence will eventually wear it down.
