And I wouldn't say hate boosts are true of all relic WS. Afterall, I've seen Namas used many times without ever pulling hate. Then again, that's the effect of it, but it proves there isn't some +enmity boosts on all relic WS. Hate was probably just shaky when Mercy Stroke or Blade: Metsu was used. Or, in the case of Mercy Stroke, using SATA with it would have a good chance of generating decent hate, but not simply because its Mercy Stroke. As far as Blade: Metsu, since any NIN at an HNM fight is going to be tanking, anyway, they're going to be close to the top of the hate list at any given time so it'd be easy to pull hate with almost anything.
But there is one really easy definitive way to test it.
Sometime mid-late fight at an HNM where the tank has had a long time to build hate, send a Kikoku NIN who hasn't previously been involved to do a single Blade: Metsu (with TP gained off adds) and see if he all of a sudden pulls hate. If he does, then its proven the effect exists, if he doesn't, then its proven that the effect doesn't exist.
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