Slowking's attack is Psyshock not Psywave. Also, having a reliable way to discard a card off their deck (like the mentioned Ursaring Prime but also Mime JR) is invaluable in this kind of deck, for whne you flip over 2 good cards and 1 you are willing to put on top, and realize next turn you may be forced to let them out of the lock.
Thanks for the note on the correction of the attack name.
RE: The top discard: it's really not that important. See, the problem is that once Slowking gets established, he's a priority 2 note, so the Weaviles are optimally already out once you start devoting resources to Slowking. The thing is that top-deck discards are good, but the limitation of the topdeck is that a single-card discard is an eschew that's viable to ignore insofar as you're careful with the hand discards.
Of course, I'm not saying it's a bad thing or a detrimental thing, but it's not really that crucial to shutting down an opponent's capacity to attack, at least, not in the context of letting them out of the lock from crucial topdecks, from my experience.
I understand.. But my point remains. This is a world class article with a glaring defect.
I've played against two different Magnerock variants, one 'straight' Magnezone and one MagneGatr variant, and the general thing is that in regards to Magnezone (and most Stage 2 decks), there is the 'warning period', which is the turn before the Candy or during the Magneton drop where you begin bracing for Magnezone.
Now, I did not include Magnezone for the reason that I did not have enough matches against it to truly consider whether I'd have an accurate projection (it was very close to nearly 50-50, but it was a smaller number of playthroughs), so I didn't provide one, but the pattern I ran across when playing Magnezone was that once it gets its momentum, it becomes difficult to combat it, but up until then, pivotal discards slowed them down enough to stunt opposition from festering.
Now, admittedly, I must confess two things. Firstly, I did some small tweaks to counter the Magnezone variant, but nothing large - the methods remained the same: simply ensured a strong line of Judges, discards, and TRTs, and you should be able to force them to play at your pace until you can appropriately counter. Donphan Prime is a viable attacker, if you wish to use him instead of Cinccino, but I would argue that Donphan is not the be-all-end-all in regards to combating Magnezone.
Secondly, Magnezone is nonexistant in my local meta, so perhaps I'm just not meeting good Magnezone players, so my observations could be faulty.