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Team meant to poison as many mons as possible, and then destroying them with crits from Pex. Defensive setup mons are common in this meta, Pex takes hits and breaks through boosts since poisoned mons get crit. It deals with all Snorlax sets, all Arcanine sets (even those with Wild Charge)...
Let me preface this by saying the team has some strange elements, but yet VGC is a metagame where seemingly silly teams are actually viable if built correctly! I win about 65-70% of my games with this team, but I'm honestly a mediocre player and I feel like someone with better intuition could do...
I know you're playing VGC soon, and in your videos you always recommend passing you teams here! I've got some description of how I've used it below the pastebin, and I hope you consider using it! https://pastebin.com/MHEjytmN