1st Casual Wifi Team; Crowd Control
Some background: I haven't touched a Pokemon game since the series' peak (imo) around the GSC days where Suicune / T-Tar / Mewtwo were in essentially every single team and were hacked to kingdom come on their Brainboys and Gamesharks. Fast forward some years later and here i am: a college student who has lots of free time in between classes so rediscovered the Pokemon franchise by purchasing a DS and the Diamond version. So far i'm pretty impressed with the depth of the game and how a black and sepia Gameboy game managed to get this far.
I'll digress a bit: i originally did not know the true value of Natures in competetive play so i releveled all of my characters (70ish atm) and then discovered this well of overpowered absurdity that is EV training. The latter is a bit too hardcore for me so i decided to forget about it at least for this group composition and leave it for a future composition.
The Lead
Gengar@Wide Lens
Ability: Levitate
Nature: Timid
-Hypnosis
-Shadow Ball
-Focus Blast
-Psychic
Due to it being one of the "old-school" pokemon at my disposal, i immediately picked it up and was pleasantly surprised at how powerful it has become. Psychic over Thunderbolt as Starmie, Gardevoir and Magnezone have Electric attacks so i can hurt any leads that are fighters (Lucario, Heracross, etc.). I chose Wide Lens as his held item because i'm sick and tired of having Focus Blast and Hypnosis miss when i need them to connnect.
Defense
Gardevoir@Leftovers
Ability: Trace
Nature: Calm
-Psychic
-Thunderbolt / Calm Mind
-Wish
-Will-O-The-Wisp
A really intriguing pokemon that has a special place in my heart. "Guardian" gives me plenty of Wish support for Garchomp who loves her Life Orb as well as adding to my Crowd Control heavy team makeup. Trace is a stupidly amazing ability that allows me to switch into Vaporeons and Electivires and cause some swear words to come out of my opponent's mouth and it gives me a clutch Intimidate on Gyarados and Salamence.
Supporters
Tangrowth@Leftovers
Ability:Chlorophyll
Nature: Impish
-Power Whip
-Leech Seed
-Knock Off
-Sleep Powder
Adds a great physical wall barring Monferno as well as providing amazing Synergy with Magnezone to devastate any steel types such as Skarmory or Metagross by taking away their Shed Shells so i'm free to have my way with them. Sleep Powder's accuracy cannot be beat and when paired with Leech Seed, it's still the same ol cheese from almost a decade ago.
Magnezone@Leftovers
Ability: Magnet Pull
Nature: Modest
-Discharge / T-Bolt
-Flash Cannon / T-Wave
-Substitute
-Magnet Rise
Okay Magnet Rise on a pokemon with 4x weakness to Ground attacks? Yes please. The main purpose of this high defense pokemon is to wall out Steel Types that my be attempting to wall my team. I can't decide whether or not to go Discharge and Flash Cannon or T-Bolt with T-Wave. The former gives me more coverage while the latter allows me to crowd control any special sweepers that may cause me trouble. Also serves as an anti-gyarados once it gets off the floor. A fun Pokemon overall.
Sweeper
Garchomp@Life Orb
Ability: Sand Veil
Nature: Adamant
-Swords Dance
-Dragon Claw
-Fire Fang / Brick Break
-Earthquake
This pokemon is a brute. After i'm done Burning/Paralyzing/Sleep'ing about a third to a half of the opposing force: Big Momma is going to town on them. After a single Swords Dance she is pretty much free to destroy anything in her path. I chose Fire Fang due to the millions of Skarmories I've encountered but with the inclusion of Magnezone i was thinking of adding a Fighting attack to counter Blisseys.
Special Sweeper
Starmie@Choice Specs
Ability: Natural Cure
Nature: Modest
-Surf
-Thunderbolt
-Ice Beam
-Psychic
My favorite thing since sliced bread met up with Peanut Butter and Jelly. I ran this same move composition back on my Blue Version and with the inclusion of the amazing Choice Specs it just screams "Let me go Supernova on someone's Face!". Bolt-Beam gives me great coverage on Dragons and Water Types while Surf helps me against Heattran and Monferno. Psychic is great against Gengar. Probably the only Pokemon i would never replace due to the amount of times its saved me from "Oh Shit" situations. I love this Pokemon.
Strategy
I'd like to think that I've calculated as much as i could in the two weeks i spent after "Beating" Pokemon Diamond by putting this team makeup but i'm sure there are holes here and there. The general gist of a battle (under perfect conditions) is that Gengar prays that the opponent doesn't open with a Weavile and sets up a Hypnosis to prevent any Stealth-Rock Leads or laying some serious hurt to those that are weak to it's attacks. Depending on the Wall i come across i send in my heavy support group to either Burn them, Sleep them, or Paralyze them and even kill them if i get a Magnezone on a steel type like Bronzong or Skarmory. This is usually when Starmie comes in for a kill or Garchomp starts doing the hokey-pokey then proceeds to rampage all over the floor. In the case that something comes to threaten my Godzilla, i bring in Tangrowth to add Leech Seed and Sleep them or Gardevoir to add in some Wishes.
This is a very Defense-heavy group without the inclusion of spikes or stealth rock which may be a bit odd because it's something that i've never seen replicated in the 5 pug matches i've done as test runs. Possibly adding a Forretress instead of Gardevoir for both Rapid Spin and Spikes would be helpful but i lose out on Burning a Physical Sweeper. Lucario or Heracross over Garchomp to counter Blissey and Snorlax but i lose out on Earthquake and Firefang which hurt Metagross/Electivire.
Some input on these substitutes or ability changes would be greatly appreciated.
Some background: I haven't touched a Pokemon game since the series' peak (imo) around the GSC days where Suicune / T-Tar / Mewtwo were in essentially every single team and were hacked to kingdom come on their Brainboys and Gamesharks. Fast forward some years later and here i am: a college student who has lots of free time in between classes so rediscovered the Pokemon franchise by purchasing a DS and the Diamond version. So far i'm pretty impressed with the depth of the game and how a black and sepia Gameboy game managed to get this far.
I'll digress a bit: i originally did not know the true value of Natures in competetive play so i releveled all of my characters (70ish atm) and then discovered this well of overpowered absurdity that is EV training. The latter is a bit too hardcore for me so i decided to forget about it at least for this group composition and leave it for a future composition.
The Lead

Gengar@Wide Lens
Ability: Levitate
Nature: Timid
-Hypnosis
-Shadow Ball
-Focus Blast
-Psychic
Due to it being one of the "old-school" pokemon at my disposal, i immediately picked it up and was pleasantly surprised at how powerful it has become. Psychic over Thunderbolt as Starmie, Gardevoir and Magnezone have Electric attacks so i can hurt any leads that are fighters (Lucario, Heracross, etc.). I chose Wide Lens as his held item because i'm sick and tired of having Focus Blast and Hypnosis miss when i need them to connnect.
Defense

Gardevoir@Leftovers
Ability: Trace
Nature: Calm
-Psychic
-Thunderbolt / Calm Mind
-Wish
-Will-O-The-Wisp
A really intriguing pokemon that has a special place in my heart. "Guardian" gives me plenty of Wish support for Garchomp who loves her Life Orb as well as adding to my Crowd Control heavy team makeup. Trace is a stupidly amazing ability that allows me to switch into Vaporeons and Electivires and cause some swear words to come out of my opponent's mouth and it gives me a clutch Intimidate on Gyarados and Salamence.
Supporters

Tangrowth@Leftovers
Ability:Chlorophyll
Nature: Impish
-Power Whip
-Leech Seed
-Knock Off
-Sleep Powder
Adds a great physical wall barring Monferno as well as providing amazing Synergy with Magnezone to devastate any steel types such as Skarmory or Metagross by taking away their Shed Shells so i'm free to have my way with them. Sleep Powder's accuracy cannot be beat and when paired with Leech Seed, it's still the same ol cheese from almost a decade ago.

Magnezone@Leftovers
Ability: Magnet Pull
Nature: Modest
-Discharge / T-Bolt
-Flash Cannon / T-Wave
-Substitute
-Magnet Rise
Okay Magnet Rise on a pokemon with 4x weakness to Ground attacks? Yes please. The main purpose of this high defense pokemon is to wall out Steel Types that my be attempting to wall my team. I can't decide whether or not to go Discharge and Flash Cannon or T-Bolt with T-Wave. The former gives me more coverage while the latter allows me to crowd control any special sweepers that may cause me trouble. Also serves as an anti-gyarados once it gets off the floor. A fun Pokemon overall.
Sweeper

Garchomp@Life Orb
Ability: Sand Veil
Nature: Adamant
-Swords Dance
-Dragon Claw
-Fire Fang / Brick Break
-Earthquake
This pokemon is a brute. After i'm done Burning/Paralyzing/Sleep'ing about a third to a half of the opposing force: Big Momma is going to town on them. After a single Swords Dance she is pretty much free to destroy anything in her path. I chose Fire Fang due to the millions of Skarmories I've encountered but with the inclusion of Magnezone i was thinking of adding a Fighting attack to counter Blisseys.
Special Sweeper

Starmie@Choice Specs
Ability: Natural Cure
Nature: Modest
-Surf
-Thunderbolt
-Ice Beam
-Psychic
My favorite thing since sliced bread met up with Peanut Butter and Jelly. I ran this same move composition back on my Blue Version and with the inclusion of the amazing Choice Specs it just screams "Let me go Supernova on someone's Face!". Bolt-Beam gives me great coverage on Dragons and Water Types while Surf helps me against Heattran and Monferno. Psychic is great against Gengar. Probably the only Pokemon i would never replace due to the amount of times its saved me from "Oh Shit" situations. I love this Pokemon.
Strategy
I'd like to think that I've calculated as much as i could in the two weeks i spent after "Beating" Pokemon Diamond by putting this team makeup but i'm sure there are holes here and there. The general gist of a battle (under perfect conditions) is that Gengar prays that the opponent doesn't open with a Weavile and sets up a Hypnosis to prevent any Stealth-Rock Leads or laying some serious hurt to those that are weak to it's attacks. Depending on the Wall i come across i send in my heavy support group to either Burn them, Sleep them, or Paralyze them and even kill them if i get a Magnezone on a steel type like Bronzong or Skarmory. This is usually when Starmie comes in for a kill or Garchomp starts doing the hokey-pokey then proceeds to rampage all over the floor. In the case that something comes to threaten my Godzilla, i bring in Tangrowth to add Leech Seed and Sleep them or Gardevoir to add in some Wishes.
This is a very Defense-heavy group without the inclusion of spikes or stealth rock which may be a bit odd because it's something that i've never seen replicated in the 5 pug matches i've done as test runs. Possibly adding a Forretress instead of Gardevoir for both Rapid Spin and Spikes would be helpful but i lose out on Burning a Physical Sweeper. Lucario or Heracross over Garchomp to counter Blissey and Snorlax but i lose out on Earthquake and Firefang which hurt Metagross/Electivire.
Some input on these substitutes or ability changes would be greatly appreciated.