>Z-recycle>Literally does nothing other than the bad added effectI can't think of any use for the majority of these moves.
>>29791799It looks like the Z-effect is added prior to the move executing normally (otherwise the "resets stats" boosting moves would be completely useless), so it's probably on the first turn. I'm not really sure if that would be drastically better than power herb - it gives the enemy time to phaze you out or set up their own stuff. The difference between +2 and +3 is only x1.25, but the boost to Def might be useful.
>>29791854Yeah, it does, meaning you'll always end at half and can always use the move, whereas regular Belly Drum + Berry gives you a chance to end up with as much as 80% of your HP but can't be used when you're under half. I think the Z-variant will be more useful generally, but all I'm saying is that some bulky mons might prefer the chance at extra health.
In addition to that, I think it's worth mentioning that things like Snorlax would often run Gluttony if they used Belly Drum, but with the Z variant they're free to use another ability instead.
