Nyah, I'm not that great with EVs, but the sets themselves...
Metagross @ Leftovers
Nature: Adamant
Moves:
Meteor Mash
Earthquake
Explosion/Sludge Bomb
Agility
CB version:
Metagross @Choice Band
Nature: Adamant
Moves:
Earthquake
Meteor Mash
Sludge Bomb
Explosion
And Stalker...
@ Leftovers
Nature: Adamant
Earthquake
Meteor Mash
Rest
Sleep Talk
There's a build featuring the elemental punches too, but I'm not positive about how that one looks like so I won't spread misinformation. Concerning EVs, it's basically maximum Attack with the rest in HP and Defense for staying power while 64 HP / 252 Attack / 104 Defense / 88 Speed should be a working spread for the Agiligross build.
Milotic @ Leftovers
Nature: Calm/Bold
Moves:
Surf
Ice Beam
Recover
Mirror Coat/Hypnosis/Light Screen/Toxic
Standard set. It should have maximum HP (252 EVs) and either maximum or near maximum Defense, depending on if you want to divert some EVs into Sp.Defense and/or Sp.Attack. Oh, and the absolute maximum for Sp.Attack EVs is apparently 52, so don't exceed it.
Stalker set:
@ Leftovers
Nature: Bold/Calm
Moves:
Surf
Toxic
Rest
Sleep Talk
This one has more staying power since the sleep condition activates Marvel Scale (+50% Defense). Maximized Defense pays off better on this one, since the bonus is a percentage, so the more the merrier.
Salamence @ Leftovers
Nature: Adamant
Moves:
Earthquake
Aerial Ace
Rock Slide/Fire Blast/Flamethrower
Dragon Dance
DDmence, definitely the most common build out there. The only spread for it that I've found at the moment is 252 Attack / 48 Defense / 48 Sp.Defense / 20 HP / 140 Speed. I wouldn't know if it's the correct one, though, I've never liked, or used, Salamence competitively. xP
@Choice Band
Nature: Adamant/Naughty
EVs: Attack: 252, Speed: 252, HP: 4
Earthquake
Rock Slide
Aerial Ace
Brick Break/Fire Blast
Just your average CBer. Fire Blast is there to handle physical walls (Primarily Skarmory) while Brick Break can help you out if your opponent has Reflect for protection. That move is pretty useless otherwise, though, so you might want to stick to Fire Blast on this one.
Gardevoir @ Leftovers
Nature: Modest (Unless you want to max out (Or nearly max out) one of the defenses with Calm or Bold)
Moves:
Psychic
Thunderbolt/Ice Punch/Fire Punch
Calm Mind
Will-O-Wisp/Hypnosis/Rest
Pretty self-explanatory, Psychic for general damaging and Thunderbolt, Ice Punch, or Fire Punch to widen your type coverage. Which one you chose depends on what you want to counter, Thunderbolt probably being the most prudent choice. For the last two moves, Calm Mind lets you buff up for some serious damaging and special walling, and the last move is for staying. Will-O-Wisp compensates for Gardevoir's rather weak Defense while Hypnosis can buy you a couple of turns for attacking or buffing. I've seen Rest on these too, so whatever floats your boat I guess. For EVs, you're going to need plenty of HP to survive and a good amount of Sp.Attack (Both stats probably well over 100) with whatever's left in Defense . and possibly some Sp.Defense - for better staying power. Another spread which I found and which may or may not be proper is 172 HP / 120 Defense / 40 Speed / 152 Sp.Attack / 24 Sp.Defense. Take that as you will.
Anyway, there you have it. Concerning suggestions for the other slots, I'll leave that to someone else (My mind's not exactly at its sharpest at the moment. xD). Oh, and you might want to wait for one of the better moveset raters to come around for EV spreads and whatnot. Good luck. ^^
