Why is Hippowdon in OU?

I've actually been wondering this for a while. It's not borderline or UU, it's in OU, yet i've rarely seen it in OU.

It might be just that I'm not high-tier yet, but why is it good? It gets countered by any grass or water types!

M venusaur checks/counters it, Contrary Serperior counters it, rotom-w checks/counters it, and keldeo counters it.

Heck, its base defense might be 8 higher than tyranitar, but their difference in sp. def is fairly large, and not to mention that tyranitar has a better attacking power, even having dragon dance which doesn't lower its speed, but raises it instead, allowing for a set-up sweep. The best hippowdon can do is curse and hope enemy doesn't have a special attacker, which will highly likely outspeed hippowdon.

Its ability is also common with tyranitar.

So... why is hippowdon in OU? Is it even useful in there?

Let me start with the tier.

Smogon tiers are usage based. In other words, how often a pokemon is used in a certain tier decides what tier it occupies. The borderline tiers are for pokemon that have been banned from the tier below it, but do not possess a high enough usage to be placed into the tier above. In other words, Hippowdon is in OU because it is used on a high enough percentage of teams.

Now, I bet you want more than that, so now let me answer the second question you asked, "Is Hippowdon viable?"

You mentioned that its base defense was only 8 points higher than Tyranitar's. However, physical bulk is a combination of two stats: Hp and Defense. While its Defense stat is not much larger than Tyranitar's, its HP is also 8 Points higher. Together with a typing more suited to sponging physical attacks, this gives the Hippo noticeably more defense.

You also mentioned a few common pokemon that destroy Hippowdon. Every pokemon has shortcomings, with exemption to a few Ubers. So while it is important to look at what beats Hippo, it is also important to look at what hippo beats. I did the hard work for you, and went down the OU tier list picking out the Pokemon that Hippo either counters, checks, or walls

Hippowdon beats these:

On paper, Hippowdon's special bulk looks terrible. however, In practice it has just enough special bulk to shut down some seriously powerful special attackers, such as the Lati twins. Keep in mind this list is only OU pokemon, and the Hippowdon set that shuts every one of these mons down is the standard smogon OU spread. I suggest you look it up. It has much more mixed bulk than purely physically defensive spreads.

While it has a common ability with Tyranitar, they play very different roles. Ttar is an attaker and Lati trapper. Hippo's job is to tank almost everything. they are both successful in their own roles, and I suggest you try them both out.

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