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Back in ORAS, the only S rank set for Clefable were calm mind + magic guard, before the raise of the support set. No one came out with the argument that it was not S because it had only one S set.
If something is extremely versatile, easy slapped on to any team, has no switch ins, is the best momentum grabber in the meta, with strong priority and great defensive typing all in the same time maybe there is a problem...