Mods/Thaumcraft/Node

Aura Nodes are the primary source of ../Vis/ in Thaumcraft. They are scattered across the landscape, including over water. They are also be found above temples or other structures (including Witch Huts. Each node has one or more types of vis that it produces, and a maximum level for each type.  Each node also has a node type (most often Normal, but Sinister nodes are also common), and also a node strength level.  The aspects of a node are random, but affected by the biome they are found in - e.g. a Node found in a desert is more likely to contain a Fire Aspect, etc.  Sinister nodes are more likely to have "dark" aspects, notably those containing Perditio.

Appearance
Nodes are faintly visible as a small shimmer in midair. With a ../Thaumometer/ or ../Goggles of Revealing/, they can be seen more clearly, and both devices can reveal their type, aspects, and current strengths. With this magical vision, nodes will show rings of color reflecting their aspects, and sometimes additional features revealing their special type.

Nodes can be broken with a hand or any tool, upon which they drop ethereal essence corresponding to their aspects. These rare drops are used in advanced magic, and are otherwise available only by killing ../Wisp/s.

Using a Node
To drain a node, a player simply has to to point their ../Wand/ at a node and right-click. When vis is drawn from a node, its strength is reduced until it regenerates, but if any type is completely drained, the node may fail to regenerate that type, or do so more slowly. (The ability to avoid damaging nodes is gained through both research, and use of more advanced wands.) A Recharge Pedestal can be used to automatically recharge a wand from any or all nodes in the vicinity. Only primal aspects of vis can be received by a wand. Nodes can also be captured ("jarred") for use elsewhere, see "Node Rooms" below.

Types
Every node has a type, which affects how it behaves. The six types of Nodes are:

Normal Nodes
The baseline, with no special behaviour.

Sinister Nodes
Sinister Nodes are commonly found embedded in an ../Obsidian Tower/, at the center of a ../Barrow/, or above an ../Obsidian Altar/. This node type creates an ../Eerie Biome/ for a small distance around it. When seen with magical vision (see below) it has a distinctive dark core. Note that the Eerie biome counts as a magical biome; It will spawn ../Angry Zombies/, ../Wisp/s and/or ../Pech/s at night, and can be used to grow ../Mana Beans/.

In addition to the above, a Sinister node will directly spawn Furious Zombies, similarly to a monster spawner. The usual limitations apply (including "dark" light levels), and if there are already four Furious Zombies present, no more will spawn until some move away or are killed.

Tainted Nodes
These nodes create a ../Taint/ed Land biome around them, which can spread outward slowly but inexorably. In magical vision, they show a purplish cloudy ring rippling out from their core. Players should be careful building their base near one, as taint spreads over time (while the chunk is loaded), and may quickly become unmanageable. In particular, spreading taint can corrupt other nodes it envelops, which then will rapidly convert the area around them.

Pure Nodes
These nodes are frequently found within ../Silverwood Tree/s. They create a ../Magical Forest/ biome around them, and can also block taint out of their immediate area, even curing already-tainted land. As of version 4.11, only nodes still in their silverwood block can create their magical biome; "naked" nodes, including those which have been jarred, cannot do so. With magical vision, they show a distinctive bright ring.

Hungry Nodes
These Nodes are Very Dangerous! This menace to life and property will pull in any entities in the vicinity and damage them. A player can easily be killed by this, especially since the pulling is quite disorienting. If a player is killed by one, their dropped items and experience will shortly be sucked in as well. They will even rip nearby blocks out of the landscape and suck those in as well. When they form in or above a structure, they will usually destroy the structure.
 * If a player is foolhardy enough to try and scan them, they will find that a hungry node keeps the aspects of all items and blocks it has absorbed. (They can also be re-scanned after gaining a new aspect!)  However, their strength in every aspect is limited to the strongest aspect they had when they spawned.
 * Detection: If found on land, their destructive habits will create a distinctive crater around them, and if the block-ripping is visible, that will also be quite distinctive.  If found over water, they may be less obvious, but squids dying in midair are a pretty good sign.
 * Hungry nodes do have some limitations -- in particular, they cannot break and suck in any block with a Hardness against mining of 5 or more. This includes most notably obsidian, but also the mineral blocks of coal, iron, redstone, emerald, or diamond. Also safe are Anvils, Iron Doors, iron bars, and Monster spawners.  Also, their suction (for blocks at least) comes in spurts, with a few safe seconds between them.

Unstable Nodes
These nodes change their strengths and even aspects over time. Notably, they occasionally drop aspect orbs at the cost of their own vis. With magical vision, they show distinctive particles radiating from their core.

Node Strength
Independently of the above types, nodes can also differ in their regeneration speed.

Bright nodes regenerate faster than normal, Pale nodes slower, and Fading nodes not at all. "Jarring" a node (capturing it for use elsewhere) will usually downgrade a node by one strength level.

Node Rooms
Nodes can also be captured within a magical build that converts them into a "Node in a Jar". This usually weakens the node (from Bright to normal to Pale to Fading) but does not change its type. When a node is jarred, its aspects are permanently limited to the levels they had when it was jarred, and will not regenerate past that point. A jarred node can be released elsewhere, typically in a "node room" built around a Recharge Pedestal. A Compound Recharge Focus can also be attached to a Recharge Pedestal, and this will allow it to draw on compound aspects, returning one point of primal vis for each point of a compound aspect that it drains.

As of version 4.11, the construction of node rooms is complicated by "node bullying", where a large node can attack and eventually consume a nearby smaller node, gaining some of its vis and even acquiring new aspects. The key points here are:
 * The Pedestal itself has a range of 8 blocks in any direction, including vertical and diagonal. That is, there can be 7 blocks space between pedestal and nodes.  This need not be empty, as the Pedestal can drain through intervening blocks.
 * The range for node bullying is only 5 blocks (4 blocks space between), so nodes must be placed every sixth block to prevent bullying.
 * Fading nodes (produced by jarring a pale or fading node) do not recover their vis, any drain is permanent. However, they can still be used to enlarge another node, by allowing the other node to consume it.

This yields an optimum design for a node room: Three levels, with spaces for nodes arranged in a cube 12 or 13 blocks on a side surrounding the pedestal, so that the pedestal can drain each of them but they cannot bully each other. (This gives places for 26 nodes.) Temporary places for "feeder nodes" can be placed further out:  These should be at least 10 blocks from the pedestal (so a fading node won't be destroyed when the pedestal is used), but within 5 blocks of a permanent node, which will consume the feeder node.

A new advanced device, Node Stabilizers, can also be placed on nodes to enhance node rooms. The basic node stabilizer prevents a node from either bullying or being bullied, but halves the recovery rate of the node. This allows simply crowding nodes further together. The advanced node stabilizer prevents a node from being bullied, but allows a large node to bully a nearby smaller one. However, it almost completely prevents recovery of vis.