Everything that can be said about what's currently "on the radar" has pretty much been said, so I'm not gonna bother repeating anything.
I do, however, have a question for the OU council (and tiering leaders for other tiers:)
what is the policy on Z-moves going to be?
There hasn't been a lot of discussion on these, but I think they're going to have a major impact on the metagame. It's something to think of for long-term but it'd be good to have a plan.
At the moment there's two good Z-move sets (Z-Rain Dance Manaphy and Z-conversion Porygon-2) that have gotten some attention, but I'm not convinced either is overpowered, nor do I believe there exists any other Z-move set at this time that is suspect worthy or even particularly prominent.
However, I think there's a high probability that Z-moves will push some pokemon over the edge, pokemon that would otherwise not be broken or even particularly amazing. Unlike Megastones, Z-crystals function on all pokemon that have a corresponding move for that crystal, so banning the crystal would be very unwise (in the same way banning Speed Boost because of Blaziken would be, but on an even greater scale.)
There are a few ways I can see Z-moves becoming a problem (
please note I'm not claiming any example sets I mention are overpowering, or even particularly good, I just want to argue that the potential for pokemon becoming too much based on the wide variety of Z-moves is there. using some example sets.)
Boosting Sets. Some of these have already gotten attention, and I mentioned two already. Z-splash and Z-celebrate/happy hour/etc. are obviously the strongest, while not having the best distribution, but I see potential for the more mundane Z-boosters to push some pokemon over the edge. For example:
- Hoopa-U, if it isn't already too strong, can now run a Rock Polish-esque set with Z-Snatch.
- Z-Electric Terrain might push a strong but not overpowering pokemon, Xurkitree, over the edge.
- Latios gets Nasty Plot through Z-Heal Block, and both Latis get it through Z-Psycho Shift, which could make them too good against more defensive teams; both also get Z-trick for a RP set.
- Z-gravity might make Landorus-I too much as well.
- Z-weathers have incredibly wide distribution, and could become a problem, especially with water and fire types, many of whom get Rain Dance or Sunny Day.
Lure Sets. Boosting is interesting, but lures will also be a major use of Z-moves. A common one I'm seeing already is Bloom Doom Heatran, which doesn't do anything new but is a direct upgrade of Power Herb Solar Beam.
But a far more problematic one is Rockium-Z Aegislash, who can use Continental Crush (200 BP with Head Smash) to OHKO Mandibuzz and Mantine without the massive recoil damage, who would otherwise be very strong checks to aegis. It's so strong that Mandibuzz has a chance to be OHKOed after rocks (Mantine is always OHKOed) even with no attack investment. Shadowball combined with Continental Crush is also enough to KO Toxapex with the right EV spread.
Now, Aegislash is already a ridiculously strong pokemon, and I think lure sets like these just make it go from arguably way too strong to definitely way too strong. But Aegislash is not the only pokemon capable of running sets like these, especially since many mediocre moves are boosted to very strong ones when used as Z-moves. Just a few I can think of right now:
- Z-Bounce (160 BP Flying) Azumarill can OHKO Mega Venusaur after some chip damage, and with Z-Dig it can OHKO Toxapex.
- Kingdra also gets bounce, and can lure grass types this way as well; Draco Meteor+Z-Bounce KO's some of rain's hardest answers, such as Mega Venusaur, Amoonguss, and AV Tangrowth, after a small amount of chip damage.
- Hyper Beam and Giga Impact have almost universal distribution, and become very strong 200 BP moves (with no recharge IIRC) with good neutral coverage that can act as lures on a lot of pokemon. For example, +2 Z-Hyper Beam allows Serperior to reliably break past Mega Venusaur. NP Thundurus is often strapped for coverage as it can't simultaneously run Grass Knot, Psychic, HP Ice, HP Flying, Focus Blast, etc. all at the same time, but +2 Z-Hyper Beam ruins most of its checks, OHKOing or very nearly OHKOing all of Lando-T, Mega Venusaur, Latias, Hippowdon, and more; Thunderbolt and Z-Hyper Beam also have a chance to beat Unaware Clefable after rocks. Toxapex is a very strong answer to CM Keldeo, but only needs a bit of chip damage to be KOed by +1 Z-Hyper Beam; many other Keldeo answers also die to this.
- Pokemon with wide movepools, like Jirachi, Mew,and Tyranitar, can potentially run a lot of lure sets, as weak moves become very strong moves when used as a Z-move
There's obviously more but you get the picture.
Nukes. Sometimes, Z-moves give a pokemon just enough power to muscle past its conventional checks, whether it be a STAB or a coverage move. This is especially true of set-up sweepers.
Going back to Aegislash, Toxapex is a good answer which can take even LO Shadowballs, but Shadowball followed up by Z-Shadowball almost always KO's after rocks. Hippowdon is always KOed by this, and 252/252+ Celesteela also has a chance to die after SR.
But other than brokesword, more pokemon can do this:
- Azumarill can check Garchomp by surviving an unboosted Earthquake and KOing with Play Rough, but Garchomp can OHKO with Z-Earthquake. Earthquake followed up by Z-Earthquake is also enough to take out Unaware Quagsire and Clefable, who would otherwise counter SD sets; +2 Z-Earthquake OHKOs basically anything that doesn't resist.
- Aegislash cannot check Tapu Lele if it's running Z-Shadowball, as Terrain boosted Psychic combined with Z-Shadowball usually OHKO's. This is also true of Jirachi.
- Manaphy no longer needs to run Psychic for Mega Venusaur, nor HP Fire for Ferrothorn; +3 Z-Ice Beam very nearly OHKO's both of them. I actually can't think of anything that would counter TG+RD+Z-Icium Manaphy, except SDef Unaware Clefable and Unaware Pyukumuku.
- Talonflame has fallen from grace, but with its high speed and Z-Brave Bird, it may still have a niche. Almost nothing can take an SD-boosed Z-Brave Bird: 252/240+ Lando-T has a small chance to die from health after rocks, Slowbro is OHKOed, p. much everything that doesn't resist just dies.
Again, you get the picture. While it is lower overall damage compared to Life Orb, Plates, Specs/Band, etc. the massive one-time damage has many uses.
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So I'm not claiming these have no downsides. They take up your item slot, and can only be used once per battle. Still, I think they're gonna have a large impact on the meta, as a lot of games are won just by removing one certain pokemon from the opponent's team. It's also entirely possibly that some pokemon's Z-sets will be too much just on their own (Manaphy certainly comes to mind, between the Z-RD and Z-Ice sets.)
It's impossible to tell at this point what will or won't be broken with the addition of Z-moves, but I think some thought should be put into the following questions:
What happens if a previously balanced pokemon becomes over-the-top by running Z-sets? This is something I definitely think is going to happen eventually. I think it's agreed that we can't ban a Z-crystal or Z-move when it's only broken on one/few pokemon, but at the same time it would be a shame to lose an OU staple because of this new mechanic, especially ones that keep many other pokemon in check (without being overcentralizing, that is.)
What happens if a move with low distribution is too strong as a Z-move? For example: in the event that Porygon-Z's Z-conversion set is found to be too strong in whatever tier, would P-Z, Conversion, or Z-Conversion be banned?
If a Z-move is inherently too strong, would it be banned, or would the most potent users of it be banned? I think Hyper Beam and Giga Impact are candidates, they hit very hard with no drawback (sans the item and moveslot,) have very good neutral coverage, and are given to virtually every pokemon. However, if they're only broken when used on a few specific sets on, say, a dozen pokemon, and fine on the other hundreds of pokemon, what gets banned?
If a Z-move is banned, would the combination of that move and its Z-crystal be banned, or would using it in battle be banned? Say for whatever reason that Z-Bulk Up is too strong on nearly anything that gets it. Bulk Up still has competitive use, unlike things like Splash or Celebrate, and conceivably one could want to run a set that includes Bulk Up and another Z-fighting move. Would this be accommodated?
That's all I can think of right now. There's certainly gonna be some decisions that have to be made.