Itachi, Plates and Element Items (Mystic Water, etc.) give a 20% boost in this generation. But eh, either way, they're still bad items. ;D Oh, and Metagross can wall effectively, don't you forget him.
Espeon @ Mind Plate
Ability: Synchronize
Nature: Naughty
Evs: Unknown, obtained through trade.
Moves:
-Psychic
-Shadow Ball
-Grass Knot
-Morning Sun
Espeon really does nothing to this team. Its not a very good special sweeper, and you've already got Gengar and PorygonZ. I suggest you take Espeon out and get a decent special wall.
Metagross @ Leftovers
Ability: Clear Body
Nature: Bold
Evs: Speed 252
Moves:
-Brick Break
-Psychic
-Meteor Mash
-Earthquake
Again, reducing Metagross's attack with Bold will harm you. Metagross needs its Attacking power to survive, so I suggest you not lower it. It needs a full EV spread, one that adds up to 508. 252 HP / 172 Defense / 84 Attack should take care of it. Now onto the subject of Psychic. If you play in-game a lot, it really does sound like a strong move. When you get to competetive, though, you will encounter a wider movepool for a Pokemon to access, thus finding more moves that would outclass Psychic. Psychic isn't bad, however, it is only frowned upon because of its terrible coverage. Another move would help Metagross more with power and support. I am suggesting Agility, for the use of the very common AgilGross. Let me explain, Metagross is a fantastic Pokemon in all of its stats except its Speed stat. It speeds stat droops at a 75, but it doesn't harm it much since it has the defenses to back it up. But if you bring its speed stat up with Agility, it will be able to outrun so many more Pokemon and hit them hard. It makes a fearsome beast with Agility. The opponent will most likely be outran and KO'd first turn, but if they're lucky enough to survive, they will try to attack Metagross, right? But even if they do attack you, they'll be attacking a Pokemon with rock hard defenses and a number of resistances too (only weak to two types!). Thats why AgilGross is highly feared upon. Now onto Brick Break, it doesn't provide much coverage. Meteor Mash and Earthquake already provide supereffective hits to all of the types Brick Break does, making it pretty unimportant to have. Thunderpunch will give a better coverage though, it hits a lot of other types with supereffective hits. I suggest Thunderpunch over Brick Break. Now summing it up, here is a moveset for Metagross.
Metagross @ Leftovers
Trait: Clear body
Nature: Impish / Adamant
EVs: 252 HP / 172 Defense / 84 Attack
- Meteor Mash
- Agility
- Thunderpunch
- Earthquake / Explosion
Gengar @ Spooky Plate
Ability: Levitate
Nature: Adamant
Evs: None
Moves:
-Thunderbolt
-Dark Pulse
-Sludge Bomb
-Shadow Ball
The whole Item subject was discussed earlier about not to use Plates. Now, Gengar is supposed to be a Special Sweeper, which means it depends on its Special Attack. Adamant would be lowering its Special Attack, one of its most important stats. Why would you do that? Gengar relies on its Special Attack, so please do not lower it. A nature like Timid will work on Gengar. And you really need to stop giving Pokemon no EVs at all. All Pokemon need EVs. Gengar gets the regular special sweeper spread of 252 SpAtk / 252 Speed / 4 HP. There is no need for Sludge Bomb. It is, in a way, similar to Psychic. It's power is pretty good but it has terrible coverage. Hypnosis would be better so it can induce sleep to its foes, and then strike it with its special sweeping power. Dark Pulse is the same as Shadow Ball, in terms of coverage. Shadow Ball is stronger due to STAB, so you only need one. Because shadow Ball is stronger, it is clearly the better choice. Take off Dark Pulse for Focus Blast to give it more coverage. In conclusion, a good Gengar moveset is this.
Gengar @ Life Orb
Trait: Levitate
Nature: Timid
EVs: 252 SpAtk / 252 Speed / 4 HP
- Shadow Ball
- Thunderbolt
- Focus Blast
- Hypnosis
Heracross @ Leftovers
Ability: Swarm
Nature: Naive
Evs: Speed 78
Moves:
-Megahorn
-Swords Dance
-Close Combat
-Stone Edge
Oi, Swarm is terrible. Guts will effect all of Heracross's moves while Swarm only effects one move. Therefore Guts is the better choice. Adamant nature please, Heracross needs the Speed Boost. Why do you give it Leftovers? Heracross isn't going to be taking many hits, so a small amount of HP recovery won't exactly help. Choice Band is the best choice for Heracross so it can strike with a lot of more power. Full EV Spread please, 252 Attack / 252 Speed / 4 HP will do. Swords Dance won't work with Choice Band, but Pursuit or Sleep Talk will do (so it can attack and get the Guts boost while asleep).
Heracross @ Choice Band*
Trait: Guts
Nature: Adamant
Evs: 252 Attack / 252 Speed / 4 HP
- Sleep Talk / Pursuit
- Megahorn
- Stone Edge
- Close Combat
*You can use the Flame Orb moveset, to activate its Guts ability. It will get the same boost from Choice Band, but it will be able to switch its moves around freely. If you do, be sure to use Pursuit instead of Sleep Talk.
Porygon - Z @ Focus Sash
Ability: Download
Nature: Docile
Evs: None
Moves:
-Discharge
-Dark Pulse
-Tri Attack
-Ice Beam
Focus Sash isn't a bad item at all, but it gets ruined but Stealth Rock and weather. Choice Scarf / Choice Specs PorygonZ are among the most feared sweepers as they can hit almost any Pokemon with a hard blow. Neutral natures (Docile) are terrible, PorygonZ would much rather get the Speed boost than having no boost at all. It needs an EV spread again. 252 Speed / 252 SpAtk / 4 HP the regular Sp. Sweeper spread. Your moveset is on the right track, but I assume you will be participating in a single battle. Thunderbolt will be the better choice with a higher power.
PorygonZ @ Choice Specs
Trait: Adaptability
Nature: Timid
EVs: 252 SpAtk / 252 Speed / 4 HP
- Thunderbolt
- Icebeam
- Dark Pulse
- Tri Attack
Claydol @ Earth Plate
Ability: Levitate
Nature: Serious
Evs: Unknown, obtained through trade.
Moves:
-Earthquake
-Psychic
-Shadow Ball
-Stealth Rock
Yeah, Earth Plate will do nothing to Claydol with a 15 point boost to one move. Leftovers is a better choice since Claydol is more of a defensive type. Again, neutral natures (Docile, Serious) are bad. Claydol probably needs a relaxed nature to get a good devensive life. If you don't know EVs of a Pokemon, there are berries to reduce EVs so you can start over. Check in the stickies for details. Psychic was explained before, it has bad coverage. Ice Beam and Earthquake has a fantastic coverage, plus it hits both physical and special walls. I suggest Ice Beam over Psychic. Shadow Ball is pretty unneccesary, I'd aim for another move like Rest, Explosion, or Cosmic Power. The team doesn't really needy of Rapid Spin, so...
Claydol @ Leftovers
Trait: Levitate
Nature: Relaxed
EVs: 252 HP / 172 SDefense / 84 Defense
- Earthquake
- Cosmic Power / Rest / Explosion
- Stealth Rock
- Icebeam
Needs a good wall in replacement for Espeon.