From Bulbapedia, the community-driven Pokémon encyclopedia.
Tall grass is a mechanic in the Pokémon main series and the habitat for many species of wild Pokémon. By entering patches of tall grass, a wild Pokémon may appear and begin to battle the player.
Tall grass is found on most routes of the Pokémon world, with some routes containing more tall grass patches than others. If the player enters a patch of tall grass, they may randomly enter a wild Pokémon battle. People are warned to stay out of tall grass if they don't have a Pokémon due to the possibility of being attacked by wild Pokémon.
In Generation I and Generation III, if Cut was used, the grass adjacent to the player would be totally erased; in Generation II, longer grass would be gradually cut shorter before disappearing. The ability to use Cut on grass was removed in Generation IV.
Differences between games
Determining the rate of encounter
The rate of Pokémon encounter is determined from a simple mathematical formula:
1 in (187.5 / ( x )) per step
Let x equal the a value which determines how rare the Pokémon is. The higher the encounter rate, the more common the Pokémon is.
| Encounter Type
|| Encounter Rate
| Very Common
- Main article: Poké Radar
The Poké Radar is a device introduced in Generation IV that is used to seek out wild Pokémon hiding in long grass. If the Pokémon that is found is knocked out or captured in a Poké Ball, a chain will begin. These chains consist of multiple members of the same Pokémon species encountered one after another. The only catch is this: a player must not encounter any Pokémon just by walking through non-wiggling grass, only by walking into the grass that shakes. Therefore, it is recommended that Repel is used in order to ensure this and achieve a higher chain. Entering the same type of grassy patch the chain was started in that is the farthest away increases the chances of meeting the same kind of Pokémon consecutively. Long chains increase the chance of finding a Shiny Pokémon, which is indicated by the patch of grass glowing white twice rather than shaking. In Generation IV, long grass does not shake when the Poké Radar is used.
Some areas in the Pokémon world have larger patches of grass than usual. These patches of grass have grown longer and more widespread than the usual grass patches, hiding many different species of Pokémon. Because of the length and thickness of the grass, it is impossible to ride a bicycle or run through the patches in Generation III, but one can run through them in Generation IV. Some trainers hide in the long grass patches, concealing themselves from view and surprising the player to a battle. Long grass was introduced in Generation II, where it was found in Johto's National Park. In Generation III, it is found on Route 119 and Route 120, in Generation IV on Route 210, and in Generation V on Route 7.
In Generation V, long grass can be normal or dark, and behaves just like standard grass: the normal one can rustle, while in the dark one double wild encounters may occur.
Seaweed, found only in Generation III, is located underwater in Pokémon Ruby, Sapphire, and Emerald, as an underwater equivalent to tall grass on land. Seaweed can be found while using Dive on dark patches of water on Route 124 and Route 126. The chance of encountering Pokémon in seaweed is lower than that of tall grass.
- Main article: Phenomenon
Rustling grass is found in Generation V, in virtually any area with patches of tall grass. Occasionally a patch of grass can be seen shaking. Entering such a patch triggers a battle with a wild Pokémon. The Pokémon found in rustling grass differ from route to route, but all areas contain Audino. In most areas, it is possible to encounter in rustling grass the evolved forms of Pokémon found in regular grass. If the player hovers around the grass for a fixed amount of time without entering it, it is possible to create a rustling grass spot at a random grass spot.
This kind of grass was introduced in Generation V. In dark grass, there is a chance of encountering two wild Pokémon at a time, who will be engaged in a double battle. Pokémon encountered in dark grass are often similar to those found in the normal grass of the route, but not identical. Often Pokémon which are rare in normal grass are more common in dark grass. Patches of dark grass are always separate from patches of normal grass. Dark grass does not rustle.
In Generation III, tall grass gives Secret Power a 30% chance of poisoning its target and gives it the appearance of Needle Arm; it causes Nature Power to become Stun Spore. Long grass gives Secret Power a 30% chance of putting its target to sleep and gives it the appearance of Magical Leaf; it causes Nature Power to become Stun Spore. Seaweed gives Secret Power a 30% chance of lowering its target's Defense and gives it the appearance of Waterfall; it causes Nature Power to become Hydro Pump.
In Generation IV, tall grass gives Secret Power a 30% chance of putting its target to sleep and gives it the appearance of Needle Arm; it causes Nature Power to become Seed Bomb.
In Generation V, tall grass gives Secret Power a 30% chance of putting its target to sleep and gives it the appearance of Needle Arm; it causes Nature Power to become Seed Bomb.
Camouflage makes the user Grass-type when used in grass, and Water-type when used in seaweed.