Mini Rules Primer #1 : Arc Nodes

Today I'm going to run through a mini rules primer on Arc Nodes and Channeling.

Arc Nodes and Channelers aren't available to everyone, but everyone should understand how they work. Lets start with an excerpt from the rulebook:

Some models, known as channelers, can act as passive relays
for spells and extend their effective range. The most common
channelers  in  WARMACHINE  are  warjacks  with  the  Arc
Node   advantage.  A  spellcaster  can  cast  spells  through
any channeler in its battlegroup that is also within its control
range.  The  spellcaster  is  still  the  model  casting  the  spell
and, if the spell is offensive, the attacker, but the channeler
becomes the spell’s point of origin (p. 40). This means that
eligible targets and the spell’s range are measured from the
channeler and that the channeling model must have line of
sight to the spell’s target. Channeling a spell does not require
the  spellcaster  to  have  line  of  sight  to  either  the  channeler
or  the  spell’s  target.  There  is  no  additional  focus  cost  for
channeling a spell.
A channeler that is stationary, knocked down, or engaged by
an enemy model cannot channel spells. A channeler can be
the target of a non-offensive spell it channels, but a spell with
a RNG of “SELF” cannot be channeled. A channeler cannot
be the target of an offensive spell channeled through it.
Make a magic attack for a channeled offensive spell normally.
The spellcaster can spend focus to boost die rolls.
Remember,  the  channeler  is  just  a  relay.  Being  used  to
channel  a  spell  is  a  passive  effect  that  occurs  during  a
spellcaster’s activation and has no impact on the channeler’s
own activation. A channeler’s focus points cannot be used to
pay the spell’s COST or boost its rolls, for example

Channelling a spell does not require the spellcaster to have line of sight to either the channeler or the spell’s target. There is no additional focus cost for channeling a spell. A channeler that is stationary, knocked down, or engaged by an enemy model cannot channel spells. A channeler can be the target of a non-offensive spell it channels, but a spell with a RNG of “SELF” cannot be channeled. A channeler cannot be the target of an offensive spell channeled through it. Make a magic attack for a channeled offensive spell normally. The spellcaster can spend focus to boost die rolls. Remember, the channeler is just a relay. Being used to channel a spell is a passive effect that occurs during a spellcaster’s activation and has no impact on the channeler’s own activation. A channeler’s focus points cannot be used to pay the spell’s COST or boost its rolls, for example. As usual, that's a lot of text to explain something intuitive. As with all games, this is to give us a tight set of rules, with no room for interpretation or argument (unlike with art, in this case more that one interpretation is a bad thing). Lets start breaking it down. If we want to use something to channel spells it must have Channeler, or the Arc Node advantage. Most of the time warjacks will be the channeler. However, there are a few warbeasts and warlocks that can access channelers (for example Minion's Blindwalker warbeast, or Skorne's Dominar Rasheth). Now that we know we can channel through a model, we have to determine if the spell is legal. So first process is to determine line of sight. A channeler (i.e. the Arc Node/model that's being channeled through) must have line of sight to the target of the spell. This can be blocked by clouds, terrain, other models. So, for example the channeler has true sight then this will allow you to ignore clouds for line of sight (Note: this also means that if the caster has true sight, but the arc node does not then you cannot ignore clouds). Another example is stealth, the channeler does not need true sight to ignore stealth as it can still draw line of sight to the model with stealth. Either the caster requires true sight if over 5 inches from the target, or the channeler must be within 5 inches of the target. This is due to the arc node being the point of origin for the spell, and how that interacts with the wording of Stealth (I.e. attacks originating more than 5inches away automatically miss). Whilst things that prevent channeling are usually self explanatory (abilities like the spell Chasten will normally specify that they prevent channeling and where that effect takes place), I will mention about everyone's favourite Cygnar Arc Node, Thorn. Thorn has a bond with Haley. It states that he can be channeled through, even if he's engaged. This is relatively simple for Haley 1 and 2, but a little more complex with Haley3 due to the presence of her Echoes (which have, as part of their rules, the ability to channel through Haley 3's arc nodes). Thorn is bonded to Haley 3 herself (Major Prime Victoria Haley) but not to the Echoes (Haley Past, and Haley Future) this leads to some interesting interactions. Haley3 can arc spells through Thorn if he's engaged, but the echoes cannot arc through Thorn if he's engaged (as he is not bonded to them). Also note that an Arc Node must be in CTRL range of the model casting the spell. This means he must be within 8 inches (or 12 inches the turn that Haley feats) to be a valid arc node for either echo.