Pokemon Scarlet and Violet just revealed a new critter in the form of Gimmighoul, whose reveal is a bit of a chicken and the egg situation. It's hard to tell whether the Pokemon GO leak showing it a few days ago was intentional or happened because a showcase was planned all along. Regardless, Gimmighoul was actually leaked prior to that over the past few months, and leakers went on to say that this was going to be one of the most powerful Pokemon in Gen 9 as a whole. The same source that correctly leaked all the currently known Gen 9 critters, named Riddler Khu, later shared that Pokemon Scarlet and Violet nerfed Gimmighoul before launch already, as its evolution supposedly had a move that was too strong.
With today's official reveal, the Pokemon Scarlet and Violet website was updated with new information regarding Gimmighoul, including confirmation that it's a Ghost-type critter, the same as Greavard, the ghost puppy. Among other details, such as the difference between Gimmighoul's Chest Form and Roaming Form, the official website also lists Rattled as the pocket monster's Ability. Rattled could be incredibly powerful on this Pokemon because it normally grants a one-stage boost to the user's Speed stat when it's hit by a damaging Bug, Ghost, or Dark-type move, and it could very well make Gimmighoul a beast in competitive battles.
How Gimmighoul's Ability Makes it a Great Attacker in Pokemon Scarlet and Violet
According to the leaks, Pokemon Scarlet and Violet will have some OP Pokemon, including Gimmighoul's evolution, which is supposedly going to be Ghost and Steel as far as its type combination goes. Whether this is confirmed or not, meaning that the critter could remain a pure Ghost-type when it evolves, it will still be weak to both Ghost and Dark-type moves, but Rattled gives it some form of leverage to make opponents think twice before attacking it with those moves.
In competitive Pokemon battles, speed is the key factor to determine which critters act first, aside from moves or Abilities that inherently make some of them acquire priority, meaning they act before others. Gimmighoul could be successfully used as an attacker with high speed and defensive held items, like Focus Sash or berries to reduce incoming Ghost or Dark damage, so that it can safely take supereffective damage and get a speed boost. On their turn, if Pokemon Scarlet and Violet players know their Gimmighoul could take Bug, Ghost, or Dark damage, they could use a set-up love to further increase its stats across the board, making it ready to sweep opponents.
Why Pokemon Scarlet and Violet's Gimmighoul Can Create a new Competitive Meta
However, this strategy can be all the more effective against teams that use Intimidate, an Ability that decreases the opponents' Attack stat when a Pokemon with it enters the battlefield. This was extremely common in competitive double battles in Gen 8 due to Incineroar, but Gimmighoul could counter that strategy in a way that prevents it from becoming meta in the first place. In fact, as of Gen 8, Intimidate actually activates Rattled even if it's not a damaging source nor a move, and that can change everything.
Pokemon Scarlet and Violet's Terastallization can also be used effectively by Gimmighoul to get opponents to proc Rattled, giving it the edge to attack first and sweep enemies. For example, as Gimmighoul's evolution is allegedly Ghost/Steel, Terastallizing this Pokemon to pure Ghost would make a lot of sense to further boost its STAB damage with those moves, and it would remove pesky weaknesses to Fire and Ground that don't work with Rattled. Overall, there's a good chance that this new Pokemon will drastically change the meta for competitive battles in Gen 9, and that's a great change from Pokemon Sword and Shield.
Pokemon Scarlet and Violet release on November 18 for Nintendo Switch.