A champion within a brush.
Locations of brush patches on 
Summoner's Rift. Not drawn to scale.
Locations of brush patches on 
Howling Abyss. Not drawn to scale.
Brush is a common feature of maps in 
League of Legends that conceals units within. The character models of units inside of a brush become transparent.
All units within a brush become hidden from view to enemies and are considered to be in the Fog of War until 
sight is granted over the area covered by the brush, such as by a 
ward. A unit inside of a brush can be revealed by all forms of sight.
Entering brush is not a form of 
stealth; it merely conceals units inside it as long as the brush is not being revealed.
Patches of brush that are connected using 
Brushmaker will act as one brush patch.
On Summoner's Rift, there are 40 patches of brush evenly distributed between both respective sides of the map. On the Ocean Rift version of the map, 2 additional patches of brush spawn near the Dragon pit and the size of some brushes are increased. On the Infernal Rift version of the map, the patches of brush surrounding the walls for the camps of 
Blue Sentinel and 
Red Brambleback are removed. On the Chemtech Rift version of the map, the patches of brush around the camps of 
Murk Wolves and Red Brambleback are removed.
On Howling Abyss, there are only 4 patches of brush, with two patches of brush near the middle of the map and a patch of brush near the outer and inner turrets for both sides.
Contents
Interacting with brush
The following abilities interact with brushes:
Akshan's Going Rogue- Caitlyn's Headshot
- Ivern's Brushmaker
- Maokai's Sapling Toss
- Nidalee's Prowl
- Qiyana's Elemental Wrath
- Rengar's Unseen Predator
- Teemo's Guerrilla Warfare
Strategy
Due to the unique properties of brush in contrast to other features on the map, there are many ways to manipulate sight using them to gain an advantage against enemies. The most notable one includes enemies becoming unable to target units inside of a brush, meaning that they must enter the brush in order to input target commands.
The key to the use of brushes is through ambush. Enemies will not know what is inside of a brush until they have gained vision over it, so it is tactical to wait inside of a brush for an unsuspecting enemy to move nearby. A traditional way of using brushes is to simply hide from enemies so as to prevent them from gaining critical information.
While inside of a brush, using targeted attacks and abilities will reveal a 450 radius centered around the champion for 4.5 seconds, so it is important to plan an ambush carefully.
Non-champion units will not trigger aggro against an enemy unless they can see them. Use this fact to determine whether or not a brush is exposed or not.
Utilizing brush
- The visual indicators and effects of some abilities, such as Nunu's Absolute Zero and Sion's Decimating Smash, are hidden while inside of an unexposed brush.
- Moving into a brush while fleeing from chasing enemies allows the manipulation of the fog of war.
- Ivern is currently the only champion who can create brush, being able to do so via Brushmaker. He can creates a line of brushes, blocking the sight of the enemy in any location.
Revealing brush
Although a unit can enter a brush to grant sight over it in any given instance, it is the most suboptimal method of doing so. Units should only enter an unexposed brush if no enemies were ever nearby in the first place, otherwise it is too dangerous. The most optimal way of revealing a brush is by letting another source of vision do it instead, such as by placing a ward inside of the brush or using an ability or spell that grants vision.
Wards will reveal the area inside of the brush as well as the area surrounding it, but not the other way around. They must be placed inside of the brush to properly grant vision of the area within.
By placing a ward inside of a brush, enemies cannot utilize that brush for concealing themselves.
Inspecting brush
Non-targeted abilities can be used to check if an enemy is inside of a brush by their visual or sound effect that is played, as well as any other conditions that occur from "hitting" like gaining a stack. Some proximity-targeted abilities can be used regardless of having sight of nearby targets or not, meaning if the ability is castable while near a brush then there is an enemy inside it.
