Riolu should most definitely be A-Rank. It is currently one of the most underrated threat in the metagame, and also one of the most underprepared for (tons of teams lack the crucial Protects or Sucker Punches, and when they have those, Riolu can play around it!). The trick right now is stacking hazards is not a very common playstyle, as Ferroseed seems to have decreased in popularity, but Staryu is also seeming to fall in popularity so I think Riolu has a lot of potential. Overall I agree with blarajan, Riolu isn't that frail, it's not *that* weak to priority if you bring it out in the right part of the game, and, by definition, it fits in A Rank because it literally can shut down 90% of the tier.
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