Hippowdon

Hippowdon, The Heavyweight Pokémon. Stones can get stuck in the ports on their bodies. Dwebble help dislodge such stones, so Hippowdon look after these Pokémon. When roused to violence by its rage, it spews out the quantities of sand it has swallowed and whips up a sandstorm.

Overview

Hippowdon is an interesting Pokemon as on paper it's a worse Tyranitar. Its pure Ground typing is overall worse than Tyranitars Rock/Dark combo due to the resistances it gets as well as the Special Defense boost from the Sandstorm it sets allowing it to answer big threats. However, if you look past this you'll find probably the most reliable weather setter in the game with access to Stealth Rock and reliable recovery. Hippowdown has all of this while bringing good coverage and support options, on top of 112 base Attack while not being weak to common moves such as Close Combat, Moonblast, and Bullet Punch. Hippowdon has traditionally been one of the best support Pokemon in Battle Stadium and Battle Spot in the past too, so when you're looking at the hippo you're looking at one of the most reliable support Pokemon out there.
Positives
-Good defensive stats backed by 112 Attack is solid and makes Hippowdon a potent member of Sand Balance
-Access to Slack Off allows Hippowdon a way to outlast other weather setters bar Pelipper
-Access to the elemental Fangs lets Hippowdon check threats such as Garchomp and Salamence, giving it some flexibility that makes it less passive.

Negatives
-Low base Speed makes it so Hippowdon will always take a hit before retaliating, which can force it to be very reactive against strong foes.
-Lack of the Sandstorm buff that its Rock-type competition gets hurts overall and makes it less tanky on the special defensive side.

Abilities

Sand Stream - Induces Sandstorm upon entering the match - This is Hippowdon's primary ability and overall is its best option as Sandstorm is the most flexible weather, providing useful utility in the form of chip damage.
Sand Force - Ground, Rock, and Steel moves gain 1.3% bonus damage in Sandstorm - Hippowdon to slow to abuse this in Singles, and it has strong competition in Doubles so this isn't very useful.

Movesets

Bulky Support

-Earthquake
-Stealth Rock
-Slack Off / Yawn
-Toxic / Whirlwind
Item Attached: Leftovers / Rocky Helmet
Ability: Sand Stream
EVs and Nature:
252 HP / 4 Atk / 252 Def
Impish Nature

Earthquake is the only attacking move that Hippowdon really needs as it hits many threats for a lot of damage, even without investment. Slack Off is the next key move as it allows Hippowdon to maintain its health throughout the match so it can just stone wall physical attackers such as Terrakion and Zeraora. Stealth Rock is a natural fit as Hippowdon can create space to set up hazards reliably and maintain them with its defensive pressure. Toxic or Whirlwind are the final options and Toxic is nice to cripple other walls or threats that try to come in on it but Whirlwind stops it from getting set up on by threats such as Volcarona. Whirlwind is preferred in Battle Stadium as Toxic isn't legal for it, and it works incredibly well with Yawn which is mandatory in Battle Stadium as well. The combined switching pressure can force foes to take a lot of chip damage or end up with a sleeping Pokemon, and Yawn alone pressures Dynamax very effectively.

Hippowdown is a bulky support so maximum bulk is the most important thing for it. Physical bulk is where it shines so naturally it works well with high HP and Defense investment, though specially defensive Hippowdon is equally viable depending on your team's needs. Leftovers gives Hippowdon extra longevity throughout the battle, though Rocky Helmet grants it even more immediate chip damage against physical attackers which is very helpful. Kee Berry is another item choice that can be considered as it greatly improves Hippwdon's matchup against physical Dynamaxers like Dracozolt who could otherwise potentially muscle through it.

Partners

-Hippowdon is one of the best support Pokemon in the Battle Stadium (when it's not banned) so realistically you can pair it with any offensive Pokemon and get good mileage out of it. Setup sweepers capitalize on the Yawn pressure it provides as well.
-Skarmory is excellent as it can create a hazard core while Hippowdon checks its answers such as Zeraora, while Skarmory can answer things such as Tapu Bulu.
-Corviknight is great much like Skarmory, but is a more offensive option and some sweeping potential with Dynamax.
-Excadrill likes the Sandstorm Hippowdon sets due to Sand Rush, making it a solid support for a Sand Rush sweep.

Countering Hippowdon

-Tangrowth just shuts Hippowdon down and can heal off most of its damage with Regenerator. Amoonguss fits in a similar boat, though it doesn't resist Earthquake like Tangrowth does.
-Urshifu is a nice answer with its Water STABs, though Surging Strikes can result in a lot of recoil against Rocky Helmet variants so be mindful of that.
-Rotom Heat/Wash/Cut is a great answer as it dodges Earthquake and can Defog away its hazards, or otherwise threaten it offensively since Hippowdon often can't do anything except Yawn or Toxic them.

Locations in Games

Red/Blue/Yellow:
Not in game

Gold/Silver/Crystal:
Not in game

Ruby/Sapphire/Emerald:
Not in game

FireRed/LeafGreen:
Not in game

Colosseum/XD:
Not in game

Diamond/Pearl/Platinum:
Route 228

HeartGold/SoulSilver:
Evolve Hippopotas

Black/White:
Evolve Hippopotas

Black 2/White 2:
Desert Resort

X/Y:
Evolve Hippopotas

Omega Ruby/Alpha Sapphire:
Trade from X/Y

Sun/Moon:
Trade from Ultra Sun/Ultra Moon

Ultra Sun/Ultra Moon:
Ultra Space Wilds

Let's Go, Pikachu!/Let's Go, Eevee!:
Not in game

Sword/Shield:
Route 8, Giant's Mirror, Lake of Outrage
Max Raid Battles: Dusty Bowl

Anime Appearences

Hippowdon has made a couple of appearances in the anime. Most notably, one is used by Bertha

# -English Episode Name- -Jap. Episode Name- Pics
533 Sleight of Sand! Pachirisu in Hippowdon's Mouth!? Pics
M11 Giratina & The Sky Warrior Giratina & The Bouquet of the Sky - Shaymin Pics
559 One Team, Two Team, Red Team, Blue Team! The Final Showdown! Pokémon Triathlon! Pics
M12 Arceus & The Jewel of Life Arceus - Towards Conquering Space-Time Pics
638 An Elite Coverup! Elite Four Bertha! Hippowdon vs Torterra!! Pics
M13 Zoroark - Master of Illusions Phantom Champion Zoroark Pics
653 Working on a Right Move! Trick Room of Terror! Ash VS Conway! Pics
M18 Hoopa & The Clash of Ages The Archdjinni of the Rings: Hoopa Pics
M19 Volcanion and the Mechanical Marvel Volcanion & The Ingenious Magearna Pics