So, I like stalling, and Sandstorm inflicts damage + gives Sp. Def boosts, so why not? UU because I think it's easier to stall with Sandstorm in UU, although I don't get Hippodown.
Hippopotas (F) @ Focus Sash
Ability: Sand Stream
EVs: 252 HP/252 Def/4 SDef
Impish nature (+Def, -SAtk)
- Stealth Rock
- Toxic
- Yawn
- Earthquake
Set-up Stealth Rock then probably dies. If it doesn't die, I either Toxic or Earthquake if it'll do major damage. I've never ever used Yawn (partly because Hippopotas doesn't survive very long), but I don't know what to put in its place, maybe Protect to buy another turn + scout. If opposing lead can Taunt, I either Earthquake if they can get hit by it, or switch out if they are immune. Against Ambipom I switch out when they Fake-out to preserve Focus Sash.
Cradily (M) @ Leftovers
Ability: Suction Cups
EVs: 252 HP/252 Def/4 SDef
Careful nature (+SDef, -SAtk)
- Confuse Ray
- Toxic
- Recover
- Rock Slide
Cradily takes hit deceptively well, as many times people switch in an attacker only to have it poisoned on the switch-in and then see their attacks do only 20%-40% with even super effective hits, then they lose to Recover + poison damage. It's also here soak up Leech Seed, and for some reason some people think this is a Bug type and Leech Seed anyway. Confuse Ray is stall plus damage all in one slot, and is chosen over Seed Bomb because Cradily often switches into Grass types.
Shuckle (M) @ Leftovers
Ability: Gluttony
EVs: 248 HP/252 Def/8 SDef
Impish nature (+Def, -SAtk)
- Toxic
- Protect
- Rest
- Knock Off
Shuckle is an insane wall, shrugging off any attacks not named Seismic Toss or Nightshade. Shuckle can Toxic a good part of the opposing team as they switch in answer after answer without any of them working. Knock Off gets rid of opposing Leftovers and gives me something to do in between Protects.
Milotic (M) @ Leftovers
Ability: Marvel Scale
EVs: 4 HP/252 Def/252 SDef
Calm nature (+SDef, -Atk)
- Surf
- Hidden Power [Electric]
- Recover
- Light Screen
Switch-in for opposing water attacks. At first I had Quagsire in this slot because of Water Absorb, but the Ground type was kind of useless as nobody would ever Thunderbolt me in the first place for me to negate the damage, and Quagsire was weak on SDef so my team was getting killed by special sweepers. I then tried Slowking but I still took decent damage if I switched into Waterfall, and its Psychic type gave it more weaknesses. Milotic takes Waterfall much better, and its only weaknesses are covered by my team. Light Screen ensures my team lives for the next little while since my team has Def pretty well covered.
Altaria (M) @ Leftovers
Ability: Natural Cure
EVs: 4 HP/252 Def/252 SDef
Impish nature (+Def, -SAtk)
- Roar
- Aerial Ace
- Heal Bell
- Roost
Roar to phaze and to make use for Stealth Rock. It also has excellent resistances to cover for the rest of my team, and also counters Blaziken with Aerial Ace. Heal Bell gets rid of Shuckle's sleep from Rest and other status from opposing Toxic and random paralysis form Thunderbolts. I chose Roost over Rest because the switch out after Rest was much too slow, and removing Altaria's flying type is pretty useful.
Steelix (M) @ Leftovers
Ability: Rock Head
EVs: 252 HP/4 Atk/252 SDef
Careful nature (+SDef, -SAtk)
- Earthquake
- Roar
- Protect
- Explosion
A second Phazer because my team loses to pretty much anything with Sword Dance or Nasty Plot that is not stopped. Explosion is to kill any problem Pokemon such as Clefable. If my opponent isn't running anything threatening I probably don't even need to switch this in. I want to try Regirock over this because it gets a SDef boost from Sandstorm, but Regirock has not Roar , or Donphan because of Rapid Spin, but Donphan doesn't take hits as well.
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I want to include a Ghost-type to negate Rapid Spin, and something with Rapid Spin to remove Stealth Rock for Shuckle and Altaria, as well as the lesser used Toxic Spikes, but I don't know what to take out. I also got killed pretty hard by Rain Dance because Hippopotas eventually dies and Milotic only lasts so long, and I don't see anyway to make up for it without losing some stuff in other match-ups.
Thanks for reading!

Hippopotas (F) @ Focus Sash
Ability: Sand Stream
EVs: 252 HP/252 Def/4 SDef
Impish nature (+Def, -SAtk)
- Stealth Rock
- Toxic
- Yawn
- Earthquake
Set-up Stealth Rock then probably dies. If it doesn't die, I either Toxic or Earthquake if it'll do major damage. I've never ever used Yawn (partly because Hippopotas doesn't survive very long), but I don't know what to put in its place, maybe Protect to buy another turn + scout. If opposing lead can Taunt, I either Earthquake if they can get hit by it, or switch out if they are immune. Against Ambipom I switch out when they Fake-out to preserve Focus Sash.

Cradily (M) @ Leftovers
Ability: Suction Cups
EVs: 252 HP/252 Def/4 SDef
Careful nature (+SDef, -SAtk)
- Confuse Ray
- Toxic
- Recover
- Rock Slide
Cradily takes hit deceptively well, as many times people switch in an attacker only to have it poisoned on the switch-in and then see their attacks do only 20%-40% with even super effective hits, then they lose to Recover + poison damage. It's also here soak up Leech Seed, and for some reason some people think this is a Bug type and Leech Seed anyway. Confuse Ray is stall plus damage all in one slot, and is chosen over Seed Bomb because Cradily often switches into Grass types.

Shuckle (M) @ Leftovers
Ability: Gluttony
EVs: 248 HP/252 Def/8 SDef
Impish nature (+Def, -SAtk)
- Toxic
- Protect
- Rest
- Knock Off
Shuckle is an insane wall, shrugging off any attacks not named Seismic Toss or Nightshade. Shuckle can Toxic a good part of the opposing team as they switch in answer after answer without any of them working. Knock Off gets rid of opposing Leftovers and gives me something to do in between Protects.

Milotic (M) @ Leftovers
Ability: Marvel Scale
EVs: 4 HP/252 Def/252 SDef
Calm nature (+SDef, -Atk)
- Surf
- Hidden Power [Electric]
- Recover
- Light Screen
Switch-in for opposing water attacks. At first I had Quagsire in this slot because of Water Absorb, but the Ground type was kind of useless as nobody would ever Thunderbolt me in the first place for me to negate the damage, and Quagsire was weak on SDef so my team was getting killed by special sweepers. I then tried Slowking but I still took decent damage if I switched into Waterfall, and its Psychic type gave it more weaknesses. Milotic takes Waterfall much better, and its only weaknesses are covered by my team. Light Screen ensures my team lives for the next little while since my team has Def pretty well covered.

Altaria (M) @ Leftovers
Ability: Natural Cure
EVs: 4 HP/252 Def/252 SDef
Impish nature (+Def, -SAtk)
- Roar
- Aerial Ace
- Heal Bell
- Roost
Roar to phaze and to make use for Stealth Rock. It also has excellent resistances to cover for the rest of my team, and also counters Blaziken with Aerial Ace. Heal Bell gets rid of Shuckle's sleep from Rest and other status from opposing Toxic and random paralysis form Thunderbolts. I chose Roost over Rest because the switch out after Rest was much too slow, and removing Altaria's flying type is pretty useful.

Steelix (M) @ Leftovers
Ability: Rock Head
EVs: 252 HP/4 Atk/252 SDef
Careful nature (+SDef, -SAtk)
- Earthquake
- Roar
- Protect
- Explosion
A second Phazer because my team loses to pretty much anything with Sword Dance or Nasty Plot that is not stopped. Explosion is to kill any problem Pokemon such as Clefable. If my opponent isn't running anything threatening I probably don't even need to switch this in. I want to try Regirock over this because it gets a SDef boost from Sandstorm, but Regirock has not Roar , or Donphan because of Rapid Spin, but Donphan doesn't take hits as well.
-------------
I want to include a Ghost-type to negate Rapid Spin, and something with Rapid Spin to remove Stealth Rock for Shuckle and Altaria, as well as the lesser used Toxic Spikes, but I don't know what to take out. I also got killed pretty hard by Rain Dance because Hippopotas eventually dies and Milotic only lasts so long, and I don't see anyway to make up for it without losing some stuff in other match-ups.
Thanks for reading!