I am using it in Showdown and it is SO good. It sweeps teams considerably easily. My general question about this thing is the same as those for Floatzel and Machamp, which is: why on earth isn't it UU?
The only reason Ambipom was ever in UU in the first place is because of a meme. Unfortunately, the truth is that Ambipom is very underwhelming and doesn't belong in UU with powerful Pokémon like Hydreigon that will easily defeat it. Ambipom is bad and cannot sweep because:
The only thing really good about Ambipom is Technician and a decent speed stat.
Because Ambipom is a weak Pokemon. It's stats isn't so good. It has no resistances. It's movepool is very bad. Fake Out+Technician is a bit good, but Meowth, Mr. Mime is the best for doing this job. It is outclassed by other normal type such as Tauros, Zangoose etc. It can be esily wear down by status moves and priority moves. It has no bulky. It's useful moves are just Knock off, Fake Out, Last Resort, Low Kick and Return. It can't defeat a Pokemon so easily, most times it struggles to faint a Pokemon. Tier system are also based on usage rate.
To be frank, Ambipom is not a great Pokemon: Technician STAB Fake Out just isn't a good enough niche. Ambipom faces stiff competition from a lot of other Normal-types, including Cinccino, Tauros, and Zangoose, (and Linoone, Stoutland, and Bewear if you're talking about UU) which boast more effective coverage and/or greater power. While Ambipom is fast, it has poor bulk and no resistances, so it must rely heavily on dealing damage while taking none in return. However, this is not easy, as Ambipom usually struggles to KO foes due to its mediocre power and its reliance on neutral coverage over super effective damage. While it can do some damage to offensive teams, it can hardly contribute against bulkier teams, while its Normal-type brethren can at least threaten both team archetypes. Ambipom is very outclassed, and other options should always be considered first.
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