Poison Pokemon tend to get lumped in with Team Rocket. There's nothing wrong with getting lumped in with Team Rocket. Jessie, James, and Meowth are the best thing that ever happened to the anime. That's why they continue happening. Again, and again, and again.
But that's the jumping-off point for many players, leaving Poison-types underappreciated in the eyes of the masses. They have a bad reputation for being one of the weakest and most pointless types in every major wing of the franchise. Pokemon Brilliant Diamond & Shining Pearl is the perfect place to turn a new leaf, with its extensive campaign giving folks plenty of time to dabble in Pokemon by the dozens.
Here's a primer on some of the best Poison-type Pokemon that BDSP has to offer. Stats, move pools, quirkier lore aspects — whatever it might take to get a poisonous partner on your roster.
5 Venusaur (National Dex)
Venusaur needs no introduction. As the first fully-evolved Grass-type starter in Pokemon history, it is one of the most universally recognizable pocket monsters around. It's easier to forget that Venusaur isn't just Grass-based, but Poison-based as well. It's a killer combination, if admittedly somewhat overdone. There is no secondary typing for Grass that is anywhere near as frequent.
That doesn't make Venusaur any less frightening in the hands of a savvy player. Its Chlorophyll ability doubles a not-terrible 80 base speed to a whopping 160 when the effects of Sunny Day are active. Furthermore, the mighty Solar Beam does not require spending a turn to charge up when this weather condition is in effect. And while it may sound disadvantageous to "waste" a turn with Venusaur setting up the effects of Sunny Day, remember that Venusaur doesn't necessarily need to be the one to do it. Many Pokemon possess the move.
Sludge Bomb is a 90 base power, special-based Poison attack that's perfect for any Poison-type with passable Special Attack. It just so happens that Venusaur is one of them. The only thing keeping Venusaur from being a world-class winner is that it can't be used during the main game. Bulbasaur won't spawn in the Grand Underground until the post-game.
4 Crobat (Sinnoh Dex)
There's an old joke about Zubats and caves. "Every two steps, a wild Zubat will appear." Except it's no joke. An exaggeration, yes, but many generations of Pokemon games feature so many Zubats that they shouldn't be classified as "common." There should be a whole separate tier that's more common than common. Perhaps it can be called "Zubat."
The point is that it's virtually impossible not to encounter a Zubat. So go ahead and catch one; they're practically begging you. Level it up to a Golbat and increase that Golbat's Happiness stat to the max. All of a sudden, that weak little bat is a powerful companion.
Crobat is a student of the late Niccolo Machiavelli. To be loved and feared in equal measure is best, but when all else fails, it is always better to be feared than loved. Crobat looks like it's going to swoop down from the dimly-lit sky at midnight on the dot, stab someone with a poisonous fang, and flitter away as quickly as it came. And appearances, in this case, are hardly deceiving.
With its outstanding Speed, promising Attack, and excellent Infiltrator ability (Light Screen and Reflect won't stop it from inflicting full damage), Crobat is a menace and a mainstay of the competitive scene. It's easy, then, to see why adding one during one's traipse across Sinnoh is a smart idea.
3 Nidoking & Nidoqueen (National Dex)
Perhaps confining two Pokemon to one entry is cheating, but it's difficult if not impossible to fully separate Nidoking from Nidoqueen. Each has a couple of perks and associated cons, but they more or less fit the same role in Pokemon BDSP. An admirable role that, like Venusaur, is only marred by the fact that neither the masculine nor feminine Nidoran can be found until after defeating the Elite Four and becoming Sinnoh League Champion.
But once that's all said and done, the Battle Tower awaits. At the Battle Tower, teams consist of not six Pokemon but a mere three, so it's imperative that players choose wisely. Having a powerful party member with the spectacular offensively-oriented typing of Poison/Ground can make a big difference in pivotal matches.
So many of your foes are going to be weak to either Poison or Ground, so it's a grand idea to dive in with a relatively bulky buddy like either of the "Nidos." They can dish out the pain with Poison Jab and Earthquake. Their Poison Point ability potentially poisons enemies who make physical contact with them, but if you're in a hurry for a debuff of that particular flavor, feel free to toss in Toxic.
2 Roserade (Sinnoh Dex)
We noted earlier that Grass/Poison is pretty prevalent. Roserade joins Venusaur in this bustling corner of the community garden but brings its own set of tools to the job. Its fantastic Special Attack and stalwart Special Defense give it an edge in both "special sweeping" and "special tanking," which are fancy ways of saying Roserade excels at striking with, and surviving against, non-physical moves.
It's hard to argue with the success Roserade can achieve with Sludge Bomb. For a Grass-type move, Energy Ball is a safe and reusable choice but if you're willing to lower Roserade's Special Attack stat two stages, Leaf Storm is like setting off a nuke in the form of a forest. Synthesis and Solar Beam will both benefit from Sunny Day, which — like Venusaur — Roserade is capable of learning.
Best of all, Budews are the Zubats of Sinnoh's grassy patches, so raising one up to Roserade can happen as quickly as those first few gyms. Three or four badges in, and some of Brilliant Diamond & Shining Pearl's tougher trainers won't know what hit them.
1 Toxicroak (Sinnoh Dex)
Toxicroak's Poison/Fighting typing gives it a defensive presence that few other Poison-types can boast, with a 50 percent reduction in damage taken from Grass, Fighting, Poison, Rock, and Dark, as well as a savory 75 percent drop in damage from Bug. That means potentially devastating attacks, such as Solar Beam, Stone Edge, Rock Slide, Focus Blast, Crunch, and Megahorn, aren't going to impact Toxicroak's durability much at all.
Typing alone can't guarantee a Pokemon's exceptional prowess, and at first glance, there's nothing about Toxicroak stats-wise that stands out to any substantial degree. But not every promising poisoner needs mile-high numerical values to thrive on the battlefield. What sets Toxicroak apart from the pack is its impeccable move pool.
Gunk Shot is a 120 base power Poison-based technique with 80 percent odds of landing the hit. That does leave the unfortunate one-in-five failure on the board, so if Sludge Bomb's more guaranteed gunk is worth the slight power reduction for you, it's a fair trade. Nasty Plot will up this wonderfully-subtitled "Toxic Mouth Pokemon" in the Special Attack department and Sword Dance can do the same for Attack. It's probably better to pick one or the other rather than risk overextension. Ice Punch and Sucker Punch fit in well with Toxicroak's overall "bad dude" aesthetic, and more importantly, they can take unsuspecting rivals by surprise.
Finally, while some readers may find this fairly unimportant, it must be noted that the whole reason Toxicroak croaks so much is to churn the poison sac in its throat for increased potency. That's kind of terrifying. Stay safe out there.