Pokemon VGC is home to various strategies, with some being more powerful than others. However, some of these strategies can be a bit overwhelming for their opponents, leading to them being dubbed as "broken."
Here are some of the 'broken strategies' that players can try out in Pokemon VGC. Keep in mind that using these techniques does not guarantee an automatic victory. However, it still takes a decent level of skill to pull these off.
5 Pokemon VGC broken strategies
1) PerishTrap

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PerishTrap is a strategy that combines the move Perish Song with the ability Arena Trap. Arena Trap prevents opposing grounded (except for Ghost-type) Pokemon from switching out, while Perish Song is a move that knocks out all mons on the field that "hear" the move and are still around after 4 turns.
Thus, the basic idea behind this strategy in Pokemon VGC is to trap opposing Pokemon and force them to "listen" to the Perish Song. Then, you must stall out turns using Protect and other moves before switching out and leaving the opponent's creatures to faint. While this strategy is dangerous in singles and is usually banned there, it's tolerated in doubles because of a greater chance of knocking out Pokemon with Arena Trap.
Due to this high knockout chance, this strategy requires a certain level of skill for players to pull off. Take Wolfe Glick, who used a Perish Trap Team to win an Invitational of over 1000 players.
Also read: 5 most innovative strategies used by Wolfe Glick in Pokemon VGC tournaments
2) Ally Switch Shedinja

Shedinja is a difficult pick for players to use in Pokemon VGC battles. While its ability Wonder Guard means it can only be damaged by super effective hits, Shedinja has only 1 HP and is weak to common VGC types like Ghost, Fire, and Dark.
Enter Ally Switch Shedinja. Ally Switch is a +2 priority move that lets players swap the positions of their Pokemon on the field. So when Shedinja uses Ally Switch, it can avoid a potential knockout while saving its teammate from a feasibly deadly move.
3) Miraidon Hyper Offense

Miraidon is an extremely powerful Legendary with STAB Dragon and Electric moves, an ability called Hadron Engine that sets up Electric Terrain to boost Electric moves, and a base 135 Special Attack stat. Keeping it as the team's main damage dealer, Miraidon Hyper Offense is meant to set things up so the dragon can easily clear the opposition in the Pokemon VGC meta.
Farigiraf's Armor Tail ability prevents priority moves like Fake Out, which could flinch Miraidon and stop it from attacking for a turn. Whimsicott can also use Encore to prevent Fake Out users from attacking more than once and can boost the side's speed with Tailwind. Finally, Fire types like Volcarona and Chi-Yu can destroy Rillaboom, who can replace Electric Terrain with Grassy Terrain.
4) Terastallized Calyrex Shadow

Calyrex Shadow is a monstrous setup sweeper in Pokemon VGC, whose main goal is to boost its already high base of 165 Special Attack by two stages with Nasty Plot. It will then spam STAB Astral Barrage, a 120 BP Ghost move that hits both opponents en route to victory, as even resistant Pokemon will struggle to tank hits at that point.
The main reason behind Terastallizing this mon is mainly for defensive purposes. For instance, Tera Fairy Calyrex Shadow tanks Wicked Blows from Urshifu Single Strike. On the other hand, Tera Normal Calyrex Shadow is a great mon who gets complete immunity from Astral Barrage coming from opposing Calyrex Shadow.
5) Armarouge

Armarouge may not seem very impressive, but what makes it threatening is that it has two main sets in the Pokemon VGC meta. At first glance, it is hard to tell which Armarouge players will face, which becomes an issue as the two styles are very different, but both are usually partnered with the Pokemon Indedee-F.
Indedee-F's main role in this strategy is to set up a Psychic Terrain with the help of its ability, Psychic Surge. As for Armarouge, there's the Trick Room set at first, which is set up easily with Follow Me support from Indeedee-F. It will then blast opponents with the move Expanding Force, which becomes 120 BP in Psychic Terrain.
However, the other set relies on Armarouge's ability Weak Armor, which boosts its Speed by two stages if a physical move hits it. This is combined with a Weakness Policy, which can boost its Attack and Special Attack by two stages if the mon is hit by a super effective move that does not kill it.
All of this leads to an obscenely powerful Stored Power, a move that becomes +20 more powerful each time a Pokemon gets a new boost. Finally, Indeedee-F will switch in to boost Stored Power (a Psychic-type move) even further, leading to the board being cleared rapidly.