Sight (Civ6)

Sight is an attribute of all units in Civilization VI and its expansions that allows them to reveal activity in nearby tiles. 
== Mechanics ==
The sight range (or sight radius) of a unit means that it can keep a number of tiles around its current location under "observation." This is achieved by lifting the fog of war from the tiles which are being "observed." Thus, all activity in these tiles will be visible to the unit's owner (and sometimes its allies).
=== Vantage points and the rule of visibility ===
This part is dedicated to vantage points and the rule of visibility in Civilization VI. In other words, it explains why a unit can or cannot see a tile within its sight radius.
The majority of land and naval units have a sight range of 2, meaning that they can "see" up to 2 tiles away from their current position, even in the late game. (There are some s which increase this to 3 - see below.) All air units have a Sight of at least 4.
Settlers and certain naval units have a sight range of 3; this helps them better explore the map. Observation Balloons, Rocket Artillery, Spies, and Naturalists also have a sight range of 3. The Settler's sight range helps players choose better spots for settling; other units' extended sight range helps them better execute reconnaissance missions, reveal more terrain with less , and spot for any land and naval units with 3 and Sight 2, which cannot fire on targets outside their vantage points even if they are in range. (See below.) The Indian Varu also has an enhanced Sight of 3.
Note, however, that not all tiles within a unit's sight radius may be visible at all times. The trick is that, quite realistically, sight can be obstructed by elevated terrain and certain features: Hills, Woods, Rainforests, and Mountains. The presence of these features within the unit's sight radius will create obstacles, which will affect visibility of certain tiles; when related to the current position of the unit we say that it has (or doesn't have) "line of sight" to these tiles. Units may overcome most line-of-sight obstacles if they stand on a "vantage point" - a tall feature which will allow the unit to see above obstacles. To better understand elevation rules, we may establish that there are four different vertical levels:
# Ground level - All flat land tiles and all water tiles (Lake, Coast, and Ocean) belong here.
# Second (vantage) level - Land tiles with Hills but without Woods or Rainforests on them belong here. This level is also known as vantage level because from it units will have visibility on most other elevation levels.
# Third (visibility blocking) level - All tiles which have both Hills and either Woods or Rainforests on them belong here. A Hill with Woods on it isn't necessarily taller, but it will still serve as hindrance for sight, as the Woods feature will block visibility for tiles behind it. Note that units standing on a Hill with Woods/Rainforest still enjoy a vantage point. The second case of third level height is Hills tiles with a defensible on top, which will be explained in the next section.
# Fourth level - Only Mountains belong here. Being the tallest feature in the game, Mountains will hide everything behind them.
Now, with elevation levels clarified, we can establish visibility rules:
* A unit always sees tiles immediately adjacent to the tile it occupies (that is, within 1 tile of its location).
* A unit sees tiles within 2 or more tiles of its location (depending on its maximum sight radius), unless they have obstacles immediately in front of them. (See below.)
* A visibility obstacle may be any of the following: a Hill (with or without Woods or Rainforest on it), a Woods feature, a Rainforest feature, or a Mountain. Note that elevation levels may add another level of complexity here.
* A unit situated on a Hill gains a vantage point and will be able to see over all terrain, unless blocked by a third or fourth level feature, such as Mountains or Hills with Woods or Rainforests on them.
* A tile with a feature which is at least one visibility level above the tile immediately in front of it will become visible to a unit, even if it is 1 tile outside its usual sight range. For example, a unit with a sight range of 2 may still see a Hill or a Mountain three tiles away. A Mountain three tiles away will be visible even if there is a Hill between it and the unit; however, if there is Woods or Rainforest on the hill, the Mountain behind won't be visible (because it is on the same level).
* Features only block visibility on tiles if these are on the same level as the blocking feature. If they are above it, they become visible. For example, let's assume the unit is on flat terrain, and there is a Hill blocking its sight. If the tile directly behind the Hill is another Hill, it will be hidden (being on the same, second level); if, however, it is a Hill with Woods on it, or a Mountain, it will be visible (being on the third and the fourth level, respectively). Since Mountains is the highest level and there are no units that can stand on a Mountains tile, Mountains always completely shield units directly behind them. Because of this mechanic, a unit on flat land with a of 2 can make a ranged attack against a unit on a Hills tile with Woods even if there's a Hills tile without Woods between them.https://www.reddit.com/r/civ/comments/17ucdyg/why_can_i_shoot_through_woods/
* City Centers and Encampments will provide a vantage point to ranged units in their tile, even though their own ranged attack won't have vantage. (More on this below.)
Note that, due to the hexagonal tile system in the game, any tile which is more than 1 tile removed from the viewer's position actually has 2 tiles lining it with the center. This makes for some tricky situations when one of these tiles has an obstacle, but the other does not. More on this below.
=== Line of sight and the rule of ballistics ===
This part is dedicated to the line of sight and the rule of ballistics in Civilization VI. In other words, it explains why a unit with ranged attacks can or cannot hit an enemy unit standing within its . It is worth noting that a unit can only shoot units that are visible, so please check out the previous part about the rule of visibility first.
* A unit with ranged attacks can always shoot the unit standing right next to it, regardless of elevation or presence of features.
* An obstacle will hide the tile behind it which forms a direct line from the unit's position. Note that obstacles only hide units behind them, not units on them. An example for this is provided in the first screenshot.
** Units with the Sentry and a of 2 can ignore Woods and Rainforests in their line of sight and make ranged attacks against units behind these features. (Outside of mods, this is only possible with Spec Ops.)
* Due to the hexagonal tile system, there are units that are only "half-hidden" by obstacles, as they are not directly behind the obstacles. Units that are "half-hidden" are not in cover.
** This may sound complicated, but for the sake of visualization, look at the first screenshot and imagine the selected Catapult belongs to Egypt instead. Now, the Kongolese Crossbowman (the one next to ỉwnw) can still shoot this Catapult, since the Catapult is only "half-hidden" by the Wooded Hills tile between them, while the other flat Plains tile reveals the Catapult.
** Again, imagine the Catapult is Egyptian and the tile the Ngao Mbeba is standing on is a Hills tile. Since the Kongolese Crossbowman next to ỉwnw is standing on a flat tile, it cannot shoot the Catapult, since the Catapult is now "half-hidden" behind two Hills tiles, which makes it fully hidden.
* Sight is also affected by elevation. In other words, some features are taller than others, and may become visible under certain circumstances (as explained above). There are ways to alter the height of a tile:
** City Centers and Encampments provide an additional level of height for units on them. For example, a City Center/Encampment on flat land will be on the "second level" while a City Center/Encampment on a Hills tile will be on the "third level."
*** Another exercise for the imagination: in the first screenshot, the Catapult cannot shoot the City Center because it is positioned on a flat tile and there is a Hills tile in between. Even if the Catapult were standing on a Hills tile, it still couldn't shoot, since the Hills tile in between has Woods on it. However, if the tile of the Catapult were a Kongolese Encampment on a Hills tile, the Catapult would be able to shoot.
*** Note that pillaged Encampments do not grant extra height.
** On defense, Encampments and City Centers do not grant height.
*** Imagine these 3 tiles directly in a line: a flat tile, an Encampment on a Hills, and a Wooded Hills (height 2.5). The unit in the Encampment on a Hills only has a height of 3 during its turn, but on the enemy's turn, it only has a height of 2 (like a normal Hills). Therefore, a unit standing on the Wooded Hills can still shoot over a Hills Encampment onto the flat tile.
** Again, ranged units inside Encampments and City Centers on Hills have a height of 3 during their turn, but the Encampments and City Centers themselves only have a height of 2. Therefore, a ranged unit inside an Encampment on Hills can shoot over a Wooded Hills, but the ranged attack of the Encampment itself cannot.
* Any units that have a of 3 or more, whether naturally or as a result of a bonus from a and/or a support unit, can lob their shots over cover and obstacles (including Mountains). This allows them to attack any target within range as long as a friendly unit or city is providing visibility. (See the second, third, and fourth screenshots for details.)
== Sight bonuses ==
There are a few ways to increase the sight radii of units:
* Spyglass, a Tier III for recon units, increases a unit's sight radius by 1.
* Rutter, a Tier II for naval melee units, increases a unit's sight radius by 1.
* Observation, a Tier III for naval raider units, increases a unit's sight radius by 1.
* Scout Planes, a Tier I for naval carrier units, increases a unit's sight radius by 1.
* Porta do Cerco, the leader ability of João III, increases all units' sight radius by 1.
* Retiring Leif Erikson (in Gathering Storm) increases all naval units' sight radius by 1.
== References ==
== See also ==
* Sight in other games
Category:Game concepts (Civ6)