Overgrowin Pokémon Polished Crystal

Overgrow is an ability that boosts the power of Grass-type moves by 50% when the user's HP is below one-third of its maximum. This makes Grass-type moves significantly more powerful in critical situations, basically allowing the Pokémon to potentially change the direction of battle when it is low on health. It is the grass counter part to Blaze and Torrent, which boost Fire and Water-type moves respectively under the same conditions. In Polished Crystal, you can find Overgrow on the grass starter Pokémon.