Brush

The Brush is the tall grassy terrain on a map that provides a champion with a form of stealth. Upon entering the brush, a champion immediately (no fade time) becomes invisible to enemy units outside of that particular patch of brush.

Gameplay
Visually, this effect manifests by your champion's avatar taking on a partially transparent quality. Opposing champions in different patches of brush will not be able to see each other even if they are within normal sight range. Brush, however, will never block your view of an allied champion hiding within.

Brush can be used in several ways to create a tactical advantage on the battlefield. First, and perhaps most apparently, one can utilize the brush to set an ambush for an enemy champion, emerging once they have passed to cut off their escape. Brush can also be used to while fleeing, breaking line of sight, and forcing pursuing champions to guess which direction you have continued. It can also be used to dodge passing minion waves, to hide your champion while he channels recall, or to force a ranged champion to close to melee range to continue their attack. Remember to use the brush to your advantage on the Field of Justice!

Wards are subject to the same limitations surrounding brush as other units. A ward placed inside a patch of brush can spot enemy units within that patch of brush and also any outside the brush that are within its range. Vision Wards placed outside of brush will not be able to see enemies inside. Because of this, it is often preferable to place wards in brush when possible.

If a skill that is not a skill shot is used while in the brush, the champion using that skill will be revealed for a short time. Your champion will also be revealed when you auto-attack from within a brush. If an ally attacks from a brush, you will also be seen.

Brush can be used to find out if the enemy has wards. If you are in the brush, not attacking, and minions begin to attack you, then they have sight into that brush. If they are not in that brush, then they must have either a ward, or a stealthed champion in it.

There was a "sweet spot" that could be found by being too close to a wall in the brush. This made you visible, because your Champion was halfway out of the brush. If a ward was placed in these spots, it would not reveal the brush. This has been fixed as of Patch 1.0.0.121

Ways to reveal areas in the Brush
There are several ways to reveal an area in brush:
 * An allied unit moves into the brush.
 * A placed in the brush will reveal within it for 3 minutes.
 * A placed in the brush will reveal within it for 3 minutes (including stealthed units).
 * The spell will reveal brush within its radius.
 * Note that the center of effect does not need to be within the brush, unlike with a ward. If any part of Clairvoyance's effect touches the brush, it will be revealed.

Reveal targeted area:

 * will reveal brush it passes over or within its explosion radius.
 * grants vision where it is cast until it is detonated.
 * grants vision where it is cast for its duration.
 * will give sight of the targeted area during flight and on landing.

Reveal enemy Champions and their immediate surroundings:

 * will reveal all enemy champions even if they are in brush.
 * will reveal nearby enemy champions who are below half health even if they are in brush (only applicable within radius of effect).

Reveal enemy Champions when hit by the ability:

 * will give sight on units poisoned by their detonation even if in brush.
 * will give sight on units poisoned by their detonation even if in brush.
 * will give sight on units poisoned by their detonation even if in brush.
 * will give sight on units poisoned by their detonation even if in brush.
 * will give sight on units poisoned by their detonation even if in brush.

Detecting enemies with Skill Shots:
If a player fires a skill shot into the brush, it won't make them visible even if you hit them. However many of them have a secondary effect or a different sound effect on impact. Here are just a few examples (not a complete list):
 * makes a splattering sound if it hits, and heals.
 * makes a distinctive sound, will reduce other cooldowns if it hits and will apply one stack of his innate ability.
 * makes a distinctive sound if it hits.
 * The target will also gain a which will enable the use of  if you are close enough.
 * makes a distinctive sound if it hits.
 * makes a distinctive sound if it hits.
 * makes a distinctive sound if it hits, as well as causing a trail to appear.
 * makes a distinctive sound if it hits.