This guide was written by ATT user Paidinfull in 2013, and has since been updated to 8th Edition by Arka0415 in 2017. To provide insights and observations behind designing your army lists with markerlights as force multipliers in mind.
In all previous Tau Codexes, Markerlights were core mechanics of the Tau army. This fact hasn’t changed in the current edition, however the unfortunate reality is that their implementation in 8th Edition is inherently flawed. The is mainly due to the fact that the benefits provided by Markerlights are not only significantly weaker than in previous editions, but many of the five different benefits they provide are also irrelevant to the majority of units in the Tau index.
However Markerlights are now cheaper, more readily available, and most importatly persist for the entirety of the shooting phase. Markerlights may only be a minor force multiplier, but they do offer distinct benefits that all Tau armies should take advantage of.
What is a Force Multiplier?
“Force multiplication, in military usage, refers to an attribute or a combination of attributes which make a given force more effective than that same force would be without it.”
To understand this thought process one first has to look at the design of our 8th Edition Index and combine those observations with some insights about unit design. A unit’s cost is always associated with a number of abilities, its statline, and the interactions between the two and then the abilities interactions with other units in the army. When one takes these facets into consideration it becomes easier to evaluate a “value” associated with a unit. However, where the multiplier facet comes in to play is how much of a return that unit can then impart onto your other forces.
A simple scenario of a force multiplier in the current Index is with the Cadre Fireblade. This unit allows each Fire Warrior to fire one additional shot at half range, for a total of three shots each with their Pulse Rifles. If a player took several squads of Fire Warriors, they would be better off investing in a Fireblade before investing in additional Fire Warriors. The logic being, each Fire Warrior is 50% more powerful when a Fireblade is nearby, making the Fireblade in fact more valuable than additional Fire Warriors. That being said, we’re not here to discuss Fireblades, but rather the function of markerlights as a “force multiplier”.
How do Markerlights function as Force Multipliers?
First, let's reference what Markerlights do. Index Xenos, p.48:
When a unit is hit by a Markerlight, place a counter next to it for the remainder of the phase. The table below describes the benefits Tau Empire models have when shooting at a unit that has Markerlight counters. All benefits are cumulative.
- 1 - Re-roll hit rolls of one for Tau Empire models attacking this unit.
2 - Destroyer and Seeker Missiles use the firing model's Ballistic Skill.
3 - Firing models suffer no penalty for moving and firing Heavy weapons, or advancing and firing Assault weapons.
4 - The target does not gain any bonus to its saving throws for being in cover.
5 - Add 1 to hit rolls for Tau Empire models attacking this unit.
The primary function of Markerlights will be to increase the accuracy of units by using benefits 1 and 5. Benefits 2, 3, and 4 are useful, but highly-situational. The cheapest Markerlight available to the Tau army is that carried by a Pathfinder, which costs a total of 8 points. Since Pathfinders have BS4+, we can assume that it costs (on average) 16 points to achieve benefit 1, and 80 points to achieve benefit 5.
Since (almost) all Tau units have BS4+, we can easily determine the statistical effectiveness of benefits 1 and 5. Benefit 1, re-rolling hit rolls of one, allows us to re-roll 16.6% of our hit rolls with a 50% for those to be successful. By adding 8.4% to 50%, we come to an accuracy of 58.4%.
Benefit 5, adding one to hit rolls, gives us an accuracy of 77.8% (when you factor in that the unit is also re-rolling hit rolls of one, as the benefits are cumulative). As such, benefit 1 gives Tau units +0.53% accuracy per point, while benefit 5 gives +0.35% accuracy per point. Given these diminishing returns, for maximum efficiency we should prioritize getting 1 Markerlight hit on each target we intend to engage, rather than 5 Markerlight hits on a single target. Of course, if there is an enemy unit which is an absolute priority target (For example, a Land Raider or Imperial Knight), then benefit 5 may become tactically viable.
The use of a Markerlight benefits is force multiplier by improving the performance of your units each turn. While it is still a force multiplier, devoting 100 points of markerlight generation to a 80-ponit squad will always show a lesser return than that a player is expecting. Use Markerlights on priority targets which you intend to engage with multiple shooting units to maximize the value of your investment.
Uses for Markerlights
Markerlights have the benefits as seen on the aforementioned table, but there are also a number of other, more tactically-nuanced ways of using those benefits. Let's consider some of the more niche applications of Markerlights.
- - Markerlights can be fired during overwatch, potentially buffing the firepower of other models.
- Benefit 1 dramatically increases the performance of models with BS2+.
- Benefit 1 significantly reduces the chance that overcharged Ion weapons will inflict damage on their carriers.
- The effect of Benefit 1 is exaggerated when models with multiple weapons use it.
- Destroyer and Seeker Missile always re-roll ones because benefits 1 comes before benefit 2.
- Benefit 2 allows Longstrike, and nearby Hammerheads, to fire Seeker Missiles with near-perfect accuracy.
- If a Seeker Missile is declared to fire, but is not fired, it is not expent.
- Benefit 3 allows a Seeker Missile to fire at full Ballistic Skill even if the carrier moved previously.
- Benefit 3 allows a Coldstar Commander to move 40" and still fire at full Ballistic Skill.
- Benefit 3 allows units to fire Markerlights at full Ballistic Skill even if they moved previously.
- Benefit 4 removes cover bonuses, including additional cover-generated save bonuses some units may have.
- Benefit 5 completely removes the chance that overcharged Ion weapons will inflict damage on their carriers.
- Benefit 5 does not make BS2+ units perfectly accurate.
- The effect of Benefit 5 is exaggerated when models with multiple weapons use it.
With that in mind let’s talk about some different Markerlight builds you can use when creating a list.
Markerlight Build Types
Markerlight-carrying units can be broken up into three categories:
The "Standard" build for Markerlights involves units with no meaningful offensive capability, which rely entirely on their Markerlights to provide value for the army.
- Standard Examples:
- Marker Drones
To use a Standard build, fire identify priority targets, and fire your Markerlights at those targets. For example, if the enemy army has a very powerful Unit A, and two reasonably dangerous Units B & C, the objective of the Standard build would be to place 5 Markerlights on Unit A, and 1 Markerlight on each of units B & C. Once these Markerlights have been placed, the rest of the models in the army can commence firing. Standard builds work best in Tau armies with high Alpha-strike damage.
The "Cascade" build type is very easy to use in 8th Edition, as Markerlight tokens are persistent until the end of the phase. A Cascade build uses units with multiple weapons, one or more of which are Markerlights. While these units fire, they fire their Markerlights as well, slowly increasing the number of Markerlight tokens on the field as you use Markerlights to make other Markerlights more accurate, and so on and so forth.
- Cascade Examples:
- Fire Warrior Shas’ui w/ Markerlight
- Stealthsuit Shas'vre w/ Markerlight & Target Lock
- Pathfinder units containing Rail Rifles or Ion Rifles
- Sun Shark Bomber
To use a Cascade build, instead of firing at priority targets, you must first decide on a firing order. Start with a Markerlight-only squad to light up targets, then fire with squads in descending order by number of Markerlights. With this method, each squad (such as Fire Warriors, Stealthsuits, and Sun Shark Bombers) fires with both Markerlights and ordinary weapons, with more and more Markerlight tokens being added to the field as the army fires, producing a "cascade" effect; hence the name. However, it may be difficult to decide on the proper firing order for the Cascade build, as your army's target priority will change as more Markerlight tokens are added to the field, and as units' shooting is successful or unsuccessful. In a Cascade build, the most powerful weapons are fired last (as the most Markerlight counters are on the field at this point), which may not be tactically-effective. This makes it difficult to ascertain which order to have units shoot in.
The "Commensal" build type was more powerful in the previous editions of Warhammer 40k (due to the presence of the infamous "Buffmander"), but due to the change in Markerlight design is now somewhat less effective. The goal of a Commensal build is to have two units function together as one, but benefiting but not adversely affecting the other. For this reason, it's been dubbed the Commensal build. As the following examples show, Commensal builds most commonly use Drone Controllers and Marker Drones.
- Commensal Examples:
- Commander w/ Drone Controller + Marker Drones
- Crisis Battlesuit team w/ Drone Controller + Marker Drones
- Broadside team w/ Drone Controller + Marker Drones
- Stealthsuit team w/ Drone Controller + Marker Drones
To use a Commensal build, follow the same firing tactics as with the Standard build. Fire your Markerlight-only Drone squads at priority targets, then commence firing with your other units. However, the trick to using a Commensal build is not in firing order, but with unit placement. Markerlights have 36" range, yet the units that may carry Drone Controllers, like Stealthsuits or Commanders, commonly have 18" range. As such, placement of the Commensal unit is important, and may bring the Marker Drones into danger they would not otherwise be in. Using a Commenal build, though, does allow for mobile, accurate, and durable Markerlights that provide benefit to their Drone Controller-carrying parent units as well as providing Markerlight support on the battlefield.
While the examples presented here are in no way exhaustive, players will find that in most cases their Markerlight build will fall under one (or more) of these three categories. Depending on that player’s preferred playstyle they may elect to go with a single particular type, a mixture of a few, or all of the above philosophies. The nice thing about the Tau Empire is that there are so many exciting and viable ways to design your army.
Please forward any thoughts and helpful critique to the Author by PM.