I'd like to call for a Suspect on Keldeo.
The first and foremost reason I call for a suspect is that there are no safe switch-ins into Keldeo except the odd Specially Defensive Gyarados (Which once again, has no other reason to invest in Special Defense than to specifically counter Keldeo).
To allow no room for speculation, I will do calcs for the entire S, A+ and A Ranks (And some "resisting" pivots below A Rank):
S Rank
0HKOed on switch. SubCM Keldeo beats FakeSpeeding variants.
Even Specially Defensive variants are 0HKOed by Specs Water Spout.
0HKOed. No explanation.
0HKOed by Specs Water Spout.
0HKOed by Specs Water Spout.
A+ Rank
Even Specially Defensive variants are 2HKOed by Specs Water Spout.
252 HP / 0 SDef variant 2HKOed by Specs Water Spout.
0HKOed. No explanation needed.
0HKOed. No explanation needed.
2HKOed. No explanation needed.
OHKOed after SR. No explanation needed.
252 HP / 0 SDef variant 2HKOed by Specs Water Spout.
0HKOed. No explanation needed.
A Rank
Outspeeds Keldeo, but beaten by Scarfed variants. Certainly cannot switch into Keldeo.
2HKOed by Specs Secret Sword.
0HKOed by Specs Water Spout.
0HKOed. No explanation needed.
Greninjas don't usually run Extrasensory. Beaten by Scarfed variants nonetheless.
Same as Diggersby. Only worse.
2HKOed by Specs Water Spout. kek.
252 HP variants 2HKOed by Specs Water Spout. Assault Vest variants 2HKOed by Specs Secret Sword.
0HKOed. No explanation needed.
0HKOed. No explanation needed.
Some pivots below A Rank:
0HKOed by Specs Water Spout.
2HKOed by Specs Water Spout.
3HKOed by Specs Water Spout. Completely beaten by SubCM variants.
2HKOed by Specs Water Spout.
2HKOed by Specs Water Spout.
2HKOed by Specs Water Spout.
Narrowly 2HKOed by Specs Water Spout. Guaranteed 2HKO after SR.
My main concern is the user of Keldeo needs not predict anything and just click Water Spout and watch things either die or get dented (Secret Sword is necessary only for Chansey), while the opponent has to either predict very correctly or simply lose a Pokemon in the process if he doesn't. This, I think is highly uncompetitive. While not as uncompetitive as King's Rock Cloyster or Chatter cancer, this one deserve the hammer too.
Discuss.