Quinn using 
Heightened Senses. Note the 
Krug camp at the top left, normally not visible from her position.
Sight is a property of units, structures, and certain summoner spells, items, and abilities in League of Legends that represents a team possessing vision of a target area. Inversely, the area of the map in which a team does not have sight over is known as the Fog of War, a common hallmark of the RTS genre which is represented visually as a dark shroud over the terrain.
Possessing sight is necessary to observe most information about any non-allied units in the game. Such information can include, among many other things, the unit's current location, direction, health, mana, possessed buffs and purchased items, making the acquisition and denial of sight one of the most crucially important skills to learn in high levels of play.
All units in the game will grant vision up to a specific radius:
- 1350: Champions, pets,
super minion, and turrets - 1200: melee, caster, and siege minions
- 1100: Zombie Wards
- 900: Totem Wards, Stealth Wards, Control Wards, and Effigies
- 500: Farsight Wards
- 450: Ghost Poros
- Disabled wards do not grant vision.
- Items and abilities do not always grant sight and those that do often have differing applications of the mechanic to one another.
There are two obstacles that exist towards regular sight - impassable terrain (which is always opaque to vision granted by units, structures and most items and abilities) and 
Brush (which is opaque towards vision when viewed from the outside inwards and not the reverse). Such barriers will also block vision of any areas that are directly behind them from the sight-granting unit. Units that can directly observe an area around these obstacles are commonly described as having line of sight towards that area.
Sight can be removed in three ways - the withdrawal of any sight-granting units, abilities or items from the vicinity, the expiration of a sight-granting debuff or spell, or directly with the 
nearsight debuff (which currently only exists with 
Graves' 
Smoke Screen, 
Nocturne's 
Paranoia, and Quinn's 
Blinding Assault). Be noted, however, that despite looking like such, 
Rek'Sai's 
Burrow does not necessarily nearsight her, as she conserves allied vision.
A pink eye symbol above a unit usually indicates true sight.
True sight is a unique form of sight linked to the detection of 
stealthed units. A unit that is stealthed is not affected by standard sight and is only visible with a source of true sight nearby. All sources of true sight currently in the game also provide standard sight - otherwise, true sight follows the same rules as standard sight. True sight does not infiltrate nearsightedness.
Obscured vision is a form of detection that does not innately reveal units nor make them targetable in any sort of way. Instead, the unit's position is distinguished through their movement patterns and silhouette. This mechanic currently only exists in Rek'Sai's Burrow, 
Oracle Lens, and 
Oracle's Extract.
Unobstructed vision is a type of sight that permeates through terrain. It allows the unit to be able to see beyond their sight radius if otherwise obstructed ( Brush). However, it can still be shrouded by nearsight. 
Kayn's 
Shadow Step and 
Aurelion Sol's 
Comet of Legend are the two only abilities that benefit from this mechanic.
The objects listed below are abilities and items that can temporarily grant sight of an area or enemy, as well as which of those abilities and items grant true sight.
Standard Sight
Area-reveal
Champion Abilities
- Akali's Twilight Shroud
- Ashe's Hawkshot and Enchanted Crystal Arrow
- Bard's Caretaker's Shrine
- Caitlyn's Yordle Snap Trap
- Cassiopeia's Miasma
- Cho'Gath's Rupture
- Corki's Phosphorus Bomb
- Darius' Apprehend
- Draven's Whirling Death
- Ekko's Parallel Convergence
- Elise's Rappel
- Ezreal's Trueshot Barrage
- Fizz's Chum the Waters
- Gangplank's Cannon Barrage
- Heimerdinger's CH-2 Electron Storm Grenade / CH-3X Lightning Grenade and H-28G Evolution Turret / H-28Q Apex Turret
- Jarvan IV's Demacian Standard
- Jayce's Shock Blast and Acceleration Gate
- Jinx's Flame Chompers! and Super Mega Death Rocket!
- Kalista's Sentinel
- Karthus' Lay Waste and Wall of Pain
- Kindred's Wolf's Frenzy
- Kog'Maw's Living Artillery
- Leona's Solar Flare
- Lux's Lucent Singularity and Final Spark
- Malzahar's Call of the Void
- Maokai's Sapling Toss and Nature's Grasp
- Miss Fortune's Make It Rain
- Nasus' Spirit Fire
- Olaf's Undertow
- Orianna's Command Attack
- Pantheon's Grand Starfall
- Quinn's Heightened Senses
- Shaco's Jack in the Box
- Soraka's Starcall
- Syndra's Force of Will
- Taliyah's Seismic Shove and Weaver's Wall
- Teemo's Noxious Trap
- Thresh's Dark Passage
- Twitch's Venom Cask
- Veigar's Dark Matter
- Vel'Koz's Tectonic Disruption
- Viktor's Death Ray and Chaos Storm
- Xerath's Eye of Destruction and Rite of the Arcane
- Yasuo's Wind Wall
- Yorick's Dark Procession
- Zed's Living Shadow and Death Mark
- Ziggs' Satchel Charge, Hexplosive Minefield, and Mega Inferno Bomb
- Zyra's Rampant Growth
Items
Jungle Plants
Unit-reveal
Champion Abilities
Items
Summoner Spells
Other
- Dragon Slayer (true damage DoT)
True Sight
Area-reveal
Items
Unit-reveal
Champion Abilities
- Caitlyn's Yordle Snap Trap and Ace in the Hole
- Fizz's Chum the Waters
- Garen's Demacian Justice
- Illaoi's Test of Spirit
- Kai'Sa's Void Seeker
- Karma's Renewal and Focused Resolve
- Kled's and Jousting
- LeBlanc's Ethereal Chains
- Lee Sin's Sonic Wave
- Lulu's Help, Pix!
- Morgana's Soul Shackles
- Nidalee's Prowl
- Rengar's Thrill of the Hunt
- Poppy's Keeper's Verdict
- Thresh's Death Sentence
- Twisted Fate's Destiny
- Zyra's Rampant Growth
