This is my idea for a Poison type monotype. It is a first draft, so please don't judge it yet, rather tell me how to improve it.
Sgt. Sludge- Muk Toxic Orb
Ability: Sticky Hold
HP 4, ATK 104, DEF 200, SpDEF 200
Nature: Impish
Moves:
Disable
Toxic
Fire punch
Poison Jab
reason: Muk is my wall. He is there to suck up damage while infecting all of their pokemon, so I gave him high defense / Special defense and toxic to drain people. Toxic Orb will heal him, and sticky hold means that no annoying knock off will stop that. Also, being poison type, he only has three issues- and fire punch can take away steel, meaning only psychic and ground can hurt this guy. Also, disable means that if you see a spammy one-shotter coming, block 'em out!
Squiddy- Tentacruel @Assault Vest
Ability: Liquid Ooze
HP 4, DEF 252, SpDEF 252
Nature: Bold
Moves:
Scald
Sludge Bomb
Ice Beam
Rapid spin
Poison has no offensive capability. However, it has incredible defense and few weaknesses, with the most irritating status effect alive. Tentacruel is yet another wall, to suck up damage while using an array of different typed moves to gain an advantage over most enemies. Also, rapid spin can clear stone edge or some other trolly set-up. And, for any who wonder, Liquid Ooze IS deliberate, I didn't forget Rain dish. It's just that sometimes, when you have drainage scrubs hiding behind leech seed, it's nice to turn it against them.
Le Frog- Toxicroak @ Choice Band
Ability: Anticipation
HP 100, 108 ATK, 100 DEF, 100 SpDEF, 100 SpD
Nature: Jolly
Moves:
Drain Punch
Return
Knock off
Thunder punch
Haha, you thought i'd give you no attackers? Nope, not that generic or evil. Toxicroak is a sweeper, with different moves and types to cover a lot of ground with boosted attack that is already high along with significant speed and some durability. While I know that it's easy to kill him, that's why he has anticipation- he can tell if they have anything good against him, so you can swap him out. This has the duel effect of making him a good entry pokemon, as he can check if they are intending to sweep you, and deal the pain at the same time.
Botany 101- Venusaur @ Venusaurite
Ability: Overgrow
HP 108, 50 ATK, 150 DEF, 50 SpATK, 150 SpDEF
Nature: Relaxed
Moves:
Earthquake
Leech Seed
Giga Drain
Synthesis
I understand the hypocracy, with me complaining about drainers earlier. But at the end of the day, it works. And Venusaur is one of the best in his league at it. Leech seed along with high defenses is good enough BEFORE Giga drain and earthquake. The attacks are almost unneccesary once the seeds are in and the Synthesis flowing. Only issue is, he doesn't take that many different types well. Luckily, Mega venusaur's Thick fat cancels out two different weaknesses ,at least to a degree- Ice and Fire, which will still hurt, but definetly won't one shot you.
Ugly Bug- Drapion @ Razor Claw
Ability: Keen Eye
HP 4, ATK 252, SpD 252
Nature: Jolly
Moves:
Swords Dance
Night slash
X- Scissor
Fire fang
Yeah, I know. He's generic and obvious. But, he's also dark type, And on my first run through, psychic types stomped my entire team. So Drapion is especially valuable, with a counter to almost all of Poison's weaknesses, and the speed, attack and near-undodgeableness to back it all up. Plus, lots of crits. We love the crits in da hood.
Drill Sgt- Nidoking @ Choice Scarf
Ability: Poison Point
HP 108, ATK 100, DEF 150, SpDEF 150
Nature: Careful
Moves:
Dragon Tail
Earthquake
Power-up Punch
Roar
So this is basically the beefcake of the team. I considered Dragalga, but Nidoking has better statistics on the whole and, to settle it mentaly, looks cooler. I mean, this brute is a killing machine. 170 ATK UNBOOSTED, this guy can OHKO almost anything. The scarf lets him move first 90% of the time, and the swapping moves mean that any potential threaght is destroyed instantly. Enjoy the team.

Sgt. Sludge- Muk Toxic Orb
Ability: Sticky Hold
HP 4, ATK 104, DEF 200, SpDEF 200
Nature: Impish
Moves:
Disable
Toxic
Fire punch
Poison Jab
reason: Muk is my wall. He is there to suck up damage while infecting all of their pokemon, so I gave him high defense / Special defense and toxic to drain people. Toxic Orb will heal him, and sticky hold means that no annoying knock off will stop that. Also, being poison type, he only has three issues- and fire punch can take away steel, meaning only psychic and ground can hurt this guy. Also, disable means that if you see a spammy one-shotter coming, block 'em out!

Squiddy- Tentacruel @Assault Vest
Ability: Liquid Ooze
HP 4, DEF 252, SpDEF 252
Nature: Bold
Moves:
Scald
Sludge Bomb
Ice Beam
Rapid spin
Poison has no offensive capability. However, it has incredible defense and few weaknesses, with the most irritating status effect alive. Tentacruel is yet another wall, to suck up damage while using an array of different typed moves to gain an advantage over most enemies. Also, rapid spin can clear stone edge or some other trolly set-up. And, for any who wonder, Liquid Ooze IS deliberate, I didn't forget Rain dish. It's just that sometimes, when you have drainage scrubs hiding behind leech seed, it's nice to turn it against them.

Le Frog- Toxicroak @ Choice Band
Ability: Anticipation
HP 100, 108 ATK, 100 DEF, 100 SpDEF, 100 SpD
Nature: Jolly
Moves:
Drain Punch
Return
Knock off
Thunder punch
Haha, you thought i'd give you no attackers? Nope, not that generic or evil. Toxicroak is a sweeper, with different moves and types to cover a lot of ground with boosted attack that is already high along with significant speed and some durability. While I know that it's easy to kill him, that's why he has anticipation- he can tell if they have anything good against him, so you can swap him out. This has the duel effect of making him a good entry pokemon, as he can check if they are intending to sweep you, and deal the pain at the same time.

Botany 101- Venusaur @ Venusaurite
Ability: Overgrow
HP 108, 50 ATK, 150 DEF, 50 SpATK, 150 SpDEF
Nature: Relaxed
Moves:
Earthquake
Leech Seed
Giga Drain
Synthesis
I understand the hypocracy, with me complaining about drainers earlier. But at the end of the day, it works. And Venusaur is one of the best in his league at it. Leech seed along with high defenses is good enough BEFORE Giga drain and earthquake. The attacks are almost unneccesary once the seeds are in and the Synthesis flowing. Only issue is, he doesn't take that many different types well. Luckily, Mega venusaur's Thick fat cancels out two different weaknesses ,at least to a degree- Ice and Fire, which will still hurt, but definetly won't one shot you.

Ugly Bug- Drapion @ Razor Claw
Ability: Keen Eye
HP 4, ATK 252, SpD 252
Nature: Jolly
Moves:
Swords Dance
Night slash
X- Scissor
Fire fang
Yeah, I know. He's generic and obvious. But, he's also dark type, And on my first run through, psychic types stomped my entire team. So Drapion is especially valuable, with a counter to almost all of Poison's weaknesses, and the speed, attack and near-undodgeableness to back it all up. Plus, lots of crits. We love the crits in da hood.

Drill Sgt- Nidoking @ Choice Scarf
Ability: Poison Point
HP 108, ATK 100, DEF 150, SpDEF 150
Nature: Careful
Moves:
Dragon Tail
Earthquake
Power-up Punch
Roar
So this is basically the beefcake of the team. I considered Dragalga, but Nidoking has better statistics on the whole and, to settle it mentaly, looks cooler. I mean, this brute is a killing machine. 170 ATK UNBOOSTED, this guy can OHKO almost anything. The scarf lets him move first 90% of the time, and the swapping moves mean that any potential threaght is destroyed instantly. Enjoy the team.