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What he's saying is, screw balance. Balance is not fun, and he wants to have fun. I get his point that this is his metagame - if you don't like it, go find one you do like. I personally hate Joimmons (no offense Joim, just my opinion) because of the lack of balance, but he has every right to...
Not only that, but it has a different support movepool (as well as the superior spore over dark void) and has access to moves like encore and leech seed over destiny bond and recover. They are honestly a lot different.
Not at all, it's weak to sapsipper mons like bouffolant. Sableye outclasses it because of destiny bond. That's not to say it isn't good, it's very good. Just not broken.
Because swellow has that delicious facade, and nature power is going to be putting a dent in most steel types. For example:
252 Atk Guts Swellow Nature Power vs. 252 HP / 0 Def Metagross: 196-232 (53.84 - 63.73%) -- guaranteed 2HKO
252 Atk Guts Swellow Nature Power vs. 248 HP / 0 Def Heatran...
Landorus is good, but it also has a lot of competition for an offensive flying type from gyarados, swellow, yanmega, tornadus, thundurus, zapdos, togekiss, and probably a bunch more that I'm forgetting.
So, swellow got a huge buff in that it got access to nature power to hit the rocks and steels that previously walled it to hell in back. May not be used though, because of the other offensive flying types that somewhat outclass it.
Minor, but somewhat interesting question: Are the moves learned through level up, or some other means. The only reason this could possibly be relevant is that shedinja would be able to have on flying move of choice it was level up (or all if they are learned on same level, which they might have...
for the threatlist:
Yanmega is one of the pokemon to gain the most from this. It gains two setup moves that are amazing on it: Quiver Dance and Tail Glow. Quiver Dance is most useful in conjunction with Tinted Lens as it allows it to run Aeroblast along with Heal Order and either a coverage move...
I think Arcanine has potential as a threat, due to it's nice power, good bulk with intimidate and sacred fire. Arcanine seems like the best sacred fire abuser, as it has coverage that makes it hard to switch into, and can fish for burns with sacred fire. It also speed ties with sawsbuck, and can...
Yes, all those pokemon are interesting, but everyone is forgetting that speed boost Yanmega gets access to both Tail Glow and Aeroblast (or hurricane if you're running rain, I guess). That makes Yanmega an insanely strong LGS due to it's ability to set up both speed and get +3 SPA at the same...