I was all gun hoe on reviewing at least half of the concepts in one go, but got tired quickly! will come back and try to review more later.
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The Heart of Stall: I like this idea and this is can be taken to some interesting places, however, I am curious how much a single pokemon might be able to transform a stall team into something that can hold up against some of the offensive nightmares that have been creeping up.
Climate Control: I like the idea of messing with weather starters, but I hope the solution doesn't turn out to be starting a different weather. There are other ways to trap opponents besides arena trap, but could they be made viable? Is shadowtag one of the only alternatives? what about trapping moves?
The Big Dipper: The idea of neutralizing parts of an enemy's "core" to get to the heart of things is fascinating, but I think the meta game is offensive enough that we may not need to explore this option at the moment. I see somethign like this using Unaware almost garunteed.
Number Cruncher: Interesting idea, but I am not sure I am qualified to comment... I'm not entirely sure where I could see this going... Just thinking of the math behind it gives me a headache already... Unless you are trying to defeat the opponent by doing exactly that?
Chill Pill: I support learning more about controlling the momentum in the game with certain pokemon. When an opponent builds up their momentum how can you stop that and slow things down in your favor? Does an example like this require a way to shut down danced up pokemon immediately or are there other strategies? slowing down the game and allowing stallers more time to do their work already
Compact movepool: This is a neat way to make a less complicated pokemon and it would be cool to add massive diversity despite as few options as possible? Will a pokemon with this design be pidgeonholed with just the best moves it has or what?
Type Equalizer: I fully support anything that brings more diversity to the table.
Ability Matchmaker: Same as above, I fully support anythign that takes uncommon thigns and brigns them to the forefront.
Ultimate Priority Abuser: I think we have enough priority abuse as it is.
Weather Balancer: I'm not sure balancing all weather is in the hands of a single 'mon.
Frostbite: Ahhh, Ice! I love the frozen status but the randomness of it can be infuriating. Not sure if there is anything in game without adding new abilities, mechanics, or moves that would be able to fix this though.
All Hail Hail: Of the weathers, this one irritates me the least at the moment and I would not be against studying a pokemon that takes advantage of this. Its possible that a 'mon like this could play a climate control-like role, but ultimately that would lead back into more weather wars.
Psych Out: After some of the recent CAPs I imagine a pokemon under this design would rely on a massive movepool so that the opponent never knows what will hit them next, not 100% sold on it, but the Mental Games it brings out is rather intriging.
Complete focus: Aren't there plenty glass cannon's and meatshields already? I think this role has been done plenty by GameFreak themselves.
One-Timer: While I like the idea of a pokemon that might only be able to pop in to be a sweeper for its first switch-in, I think a support mon or staller needs the versatility of moving in and out of battle, this concept would only hurt those signficantly and make a great premier sweeper.
Offense-breaker: Would this pokemon simple have astronomical defensive stats, perfect typing, and rely on toxic or burn to do its dirty work?
Sacrifice: Initially I think this idea is terrible from a part of the general description "a pokemon that is better for the team dead." There is no case of that, but the "(or dying)" is a possible direction to explore. Maybe an ability like Curse (on a ghost Type), Curse Song, or Lunar Dance (after a few ticks of curse). I would be fascinated by a Ghost type that uses poison heal and curse to do some damage, but in the end is that even the direction a pokemon with those moves would take?
Weather Warrior: I don't think we need more pokemon that can make use of rain dance or sunny day or Sand storm. Didn't Mollux end up fillign this role by being great in rain dance with dry skin and otherwise beign great in sun with fire abilties and solar beam?
Faustian Bargain: After reading this I immediately thoguth of the complete focus concept from above, but I am curious more about the "maybe somethign else, by creating a rical that lacks that trait." I would really be interest to see where a concept in that direction could be taken.
Small But Terrible: I just love this idea because it seems to want to walk away from the power creep but stay useful.
Leading the Charge: Hmmmmmmm, This one is neat but so difficult to pull off because of game mechanics.