I've been playing with a sandstorm team for a while and I wanted to use a favorite of mine, Cacturne. Cacturne has 115 attack with a great movepool and typing capable of dealing massive damage to a un-prepared player.
@ Leftovers
Impish
252 HP / 252 Defense / 6 Special Defense
Earthquake
Ice Fang
Stealth Rock
Slack Off
Hippowdon sets up the sand, and ass bones most physical attackers. Stealth Rocks eliminates opposing Focus Sasher and tears open Gyarados and Salamences. Blah Blah Blah. Standard Hippo.
@ Leftovers
Impish
252 HP / 252 Defense / 6 Special Defense
Knock Off
Toxic
Rest
Encore
Shuckle becomes nearly inpenatrable in a sandstorm. Only the strongest of attacks can bring him down. Shuckle paired with Hippowdon do a good job of walling nearly every pokemon in the game. Encore gives Cacturne and Relicanth free switch-ins as well as messing with stat-uppers.
@ Choice Scarf
Adamant
252 Speed / 252 Attack / 6 HP
Waterfall
Earthquake
Stone Edge
Ice Fang
Scarf Gyarados is underrated. Starmie and Gengar are both outrun and easily 2HKOed. Gyarados can still hit moderately hard even without any real boosts. The blue worm helps me against things I would otherwise have trouble with, like SD Lucario, Infernape, Salamence and Garchomp. It has a annoying habit of dying though. Its comparably the most frail thing on my team when you consider how its used.
@ Leftovers
Timid
Standard EVs
Thunderbolt
Ice Beam
Recover
Rapid Spin
Probably the least useful member of my team. He counters Gyarados and revenge kills non-DD Dragons. Not much else. Rapid Spin is nice, and really does help Gyarados and Shuckle but I can't help but think there are other pokemon that can fill this role better. Hell, Forretress can Rapid Spin and just Explode on the pokemon I want this Starmie to counter (Gyarados mostly). Actually Forretress would help my odd grass weakness.
@ Choice Band
Adamant
252 Attack / 252 HP / 6 Defense
Head Smash
Aqua Tail
Earthquake
Yawn
With 252 HP EVs, great base defense and a SD Sandstorm boost Relicanth is remarkably tough. He can shrug off Starmie Thunderbolts and even Choice Band Earthquakes. His firepower is incredible, 2HKOing most things with a combination of Head Smash and Aqua Tail. Earthquake is sort of filler, but Yawn is sometimes useful. Relicanth tries to come in on Shuckles Encores then simply beats the incoming walls to death. Once Relicanth finally falls, its Cacturnes turn.
@ Leftovers
Adamant
252 HP / 252 Attack / 6 Special Defense
Sucker Punch
Focus Punch
Substitute
Swords Dance
A real terror when set up. Cacturne sets up a sub, either from Shuckle's Encore or from forcing a switch. Then it either Focus Punches or Swords Dances followed by Sucker Punch. This is coming from a pokemon with more attack then Lucario, and with STAB Sucker Punch. You don't realize how scary STAB Sucker Punch is until it brings down a Gyarados is one hit. Once Cacturne is in a position to be hit, it switches out. By then it usually gains back the HP it lost from Substitute. Very few things counter this without good prediction. Even Hippowdon can be taken out, even though it turns into a prediction war (Sucker Punch and Focus Punch 2HKO when SDed. Hippowdon needs to switch between Ice Fang and Slack Off carefully).

Impish
252 HP / 252 Defense / 6 Special Defense
Earthquake
Ice Fang
Stealth Rock
Slack Off
Hippowdon sets up the sand, and ass bones most physical attackers. Stealth Rocks eliminates opposing Focus Sasher and tears open Gyarados and Salamences. Blah Blah Blah. Standard Hippo.

Impish
252 HP / 252 Defense / 6 Special Defense
Knock Off
Toxic
Rest
Encore
Shuckle becomes nearly inpenatrable in a sandstorm. Only the strongest of attacks can bring him down. Shuckle paired with Hippowdon do a good job of walling nearly every pokemon in the game. Encore gives Cacturne and Relicanth free switch-ins as well as messing with stat-uppers.

Adamant
252 Speed / 252 Attack / 6 HP
Waterfall
Earthquake
Stone Edge
Ice Fang
Scarf Gyarados is underrated. Starmie and Gengar are both outrun and easily 2HKOed. Gyarados can still hit moderately hard even without any real boosts. The blue worm helps me against things I would otherwise have trouble with, like SD Lucario, Infernape, Salamence and Garchomp. It has a annoying habit of dying though. Its comparably the most frail thing on my team when you consider how its used.

Timid
Standard EVs
Thunderbolt
Ice Beam
Recover
Rapid Spin
Probably the least useful member of my team. He counters Gyarados and revenge kills non-DD Dragons. Not much else. Rapid Spin is nice, and really does help Gyarados and Shuckle but I can't help but think there are other pokemon that can fill this role better. Hell, Forretress can Rapid Spin and just Explode on the pokemon I want this Starmie to counter (Gyarados mostly). Actually Forretress would help my odd grass weakness.

Adamant
252 Attack / 252 HP / 6 Defense
Head Smash
Aqua Tail
Earthquake
Yawn
With 252 HP EVs, great base defense and a SD Sandstorm boost Relicanth is remarkably tough. He can shrug off Starmie Thunderbolts and even Choice Band Earthquakes. His firepower is incredible, 2HKOing most things with a combination of Head Smash and Aqua Tail. Earthquake is sort of filler, but Yawn is sometimes useful. Relicanth tries to come in on Shuckles Encores then simply beats the incoming walls to death. Once Relicanth finally falls, its Cacturnes turn.

Adamant
252 HP / 252 Attack / 6 Special Defense
Sucker Punch
Focus Punch
Substitute
Swords Dance
A real terror when set up. Cacturne sets up a sub, either from Shuckle's Encore or from forcing a switch. Then it either Focus Punches or Swords Dances followed by Sucker Punch. This is coming from a pokemon with more attack then Lucario, and with STAB Sucker Punch. You don't realize how scary STAB Sucker Punch is until it brings down a Gyarados is one hit. Once Cacturne is in a position to be hit, it switches out. By then it usually gains back the HP it lost from Substitute. Very few things counter this without good prediction. Even Hippowdon can be taken out, even though it turns into a prediction war (Sucker Punch and Focus Punch 2HKO when SDed. Hippowdon needs to switch between Ice Fang and Slack Off carefully).