This optional rules module is intended to facilitate military operations on a grander scale – planetary invasions, uprisings, and protracted warfare. It leans heavily on the original 1990 Mighty Empires, pdf versions of which are quiet readily available after Games Workshop released them for free around the time of the 2007 edition with its far more rudimentary rules.
Scale
As planetary campaigns are map-driven, some thought should go into scale. Recommendations are 60 kilometer hexes (edge to edge) with 1 week turns, 300 kilometer hexes with 1 month turns, or (if planetary battles and sieges are to be fought, but not intended to be in focus) condensing the entire planet into one single “hex” using nominal 1 year turns (though some fights might be resolved in far less time).
You may map out only a relevant part of the planet or the entire world, in which case mapping onto an unfolded icosahedron is recommended.
Terrain and Features
For the movement rules it is important for the map to show terrain that is impassable or dangerous for large bodies of troops to cross. Also the locations of any important special features, such as spaceports, settlements, dig sites, mining complexes, planetary defense silos, and similar should be noted. Some features may be hidden or otherwise unknown to the characters.
Armies
The position of armies are tracked on the planetary map. Armies follow standard Epic army compostion, consisting of a minimum of 1 company card of troops and up to 1 special and 5 support cards per company card. A single army may contain a maximum of 2,500 points of troops. Warbands operating with an army do not count against this maximum. Record the exact composition of each army, as well as noting any permanent losses from individual cards. Multiple armies may operate together. For some special force compositions, it might be considered permissible to spread cards across multiple armies (e.g., a titan heavy army in excess of 2,500 points may have only a single battlegroup as its sole company card and thus be unable to fulfill the normal minimum requirements for a second army), but these armies then always have to operate together.
Forces
The difference between a force and an army is that a force is not formed up for movement and battle on the map. It is instead a pool of available troops, from which one or more armies may be formed.
The troops available can be expressed either as a points budget along with factions and possible restrictions (e.g., a force consisting of 5,000 points of Imperial Guard with no super-heavies, or a force consisting of 2,000 points of Squat infantry plus 1,000 points of Tech Guard), or by directly listing the type and number of army cards (where possible, use company cards instead of multiples of support cards) but without having to assign support and special cards to individual companies (e.g., a force consisting of 10 Imperial Guard tactical companies, 4 Imperial Guard support companies, 1 Imperial Guard Leman Russ company, and 2 Imperial Guard Stormblades).
The location of a force should be indicated on the map, this being their primary mustering ground and depot location.
Surface Movement
Similarly to Mighty Empires, the movement of armies involves two distinct steps – scouting of the route followed by the actual movement of the main body of troops.
An army may scout up to 1 hex per turn for every full 10cm of Move of its fastest unit (an army that has no units with at least 10cm of Move may not scout and will be reliant on other armies in the same hex for this, otherwise it will be rendered immobile), units mounted in transports may use the transport’s Move for the purpose of determining Move. The retinue may opt to scout, in which case the number of hexes that can be scouted is determined based on the retinue’s Move, a scouting retinue is is not accompanied by any of its warband.
To scout a hex, nominate a hex adjacent to either the hex the army is in or to a hex that was just successfully scouted. You may not nominate the same hex twice in the same turn. After nominating a hex, make a Navigate (Surface) test (if the retinue is not accompanying the scouts, assume that the armies scouts possess the skill at no modifier, i.e. roll using the Morale Value of the army’s fastest unit), circumstances may impose a bonus or penalty on this roll (e.g., a friendly ship in low orbit may assist with real time sensor scans giving +1, or permanent storms may impose a -1 penalty). If the test is successful, the hex has been successfully scouted.
If the retinue is scouting and a successfully scouted hex contains hostile armies, make either an Observation skill test (when trying to gather information on the enemy from a save distance) or a Stealth skill test (when trying to infiltrate as closely as possible to gather detailed intelligence).
If the Observation skill test is successful, reveal the total number of cards and the number of company cards of the enemy armies and the biggest faction amongst them as well as whether any titans are present.
If the Observation skill test was unsuccessful, reveal one faction as the retinue briefly skirmishes with outriders and retreats.
If the Stealth skill test is successful, reveal the exact composition of the enemy armies.
If the Stealth skill test was unsuccessful, roll for Casualty Recovery with a +1 bonus. If one or more characters are captured, the enemy obtains information on the friendly armies (most likely the number of company cards).
Alternatively, play out the scouting and infiltration in detail.
If the retinue was not acting as the scouts and a successfully scouted hex contains hostile armies, roll a D6 and consult the chart below instead.
| D6 | Result |
| 1 | Enemy outriders spot the scouts and drive them off in a sharp skirmish before useful intelligence can be gathered. At least one scout is captured and reveals information on the friendly armies (most likely the number of company cards). |
| 2 | Enemy outriders spot the scouts and drive them off before useful intelligence can be gathered. |
| 3 | Enemy outriders spot the scouts and drive them off, but some intelligence can be gathered. The total number of company cards of the enemy armies and one faction are revealed. |
| 4-5 | The scouts fight off enemy outriders, managing to gather solid intelligence before escaping. Reveal all factions with at least one company card present in the enemy armies as well as the number of cards and of company cards per faction. |
| 6 | The scouts avoid contact with enemy outriders and gather detailed intelligence before retreating unseen. Reveal the exact composition of the enemy armies. |
After scouting is complete, the army may move 1 hex per turn for every full 10cm of Move of its slowest unit (minimum 1 hex), units mounted in transports may use the transport’s Move for this purpose. It may enter only hexes that have been successfully scouted this turn.
An army may be force marched 1 additional hex, in which case roll a D6 and consult the chart below.
| D6 | Result |
| 1 | Lose D6x100 points of troops and D6 points of supplies |
| 2 | Lose D6x100 points of troops and D3 points of supplies |
| 3 | Lose D6x50 points of troop and 1 point of supplies |
| 4 | Lose 1 point of supplies |
| 5-6 | No effect |
When an army would need to enter or cross dangerous terrain as it moves, make a roll on the chart below.
| D6 | Result |
| 1-2 | The army makes no progress and is unable to move any further this turn. |
| 3-4 | The move through the dangrous terrain incurrs the risk of substantial loses, roll on the Forced March Chart above. |
| 5-6 | A safe route is established and the army can complete its move without danger. |
If an army ends up in a hex containing enemy armies, battle is joined.
Abstracted Battles
When opposed armies meet in battle, you may either play the battle out using Epic rules, or use the battle rules from Mighty Empires with the following adjustments:
Double all strength values on the Combat Table.
Before choosing battle plans, both armies test Command. If one army succeeds and the other fails, the failing army must choose and reveal its battle plan before the successful army chooses its plan.
In addition to the strategic modifier from battle plans, modify by 1 in favour of an army for every two troop types (from the list of infantry, walker, cavalry, vehicles, flyers, knights, super heavy vehicles, and titans) that it fields and that the opponent does not field.
Instead of character casualties, a roll of doubles for the random modifier indicates the loss of a high value target, this might be the retinue (in which case roll for Casualty Recovery), a unit represented by a special card, a titan, a commissar, or some other stand out part of the affected army.
Double all points losses from the Battle Result Chart.
Double all points losses from the Pursuit Chart. A roll of 3 may mean the retinue is captured if appicable.
Especially in the lead-up to a battle the retinue – and warband – may try to influence things by embarking on raids, sabotage missions, or espionage operations, to eliminate key enemy assets, learn of battle plans in advance, or any number of other goals.
Fortresses & Sieges
Again following the rules from Mighty Empires, defending armies may retreat into suitable defensive features, such as fortresses, citadels, or shield-domed cities.
Apply all relevant adjustments (such as the doubling of indicated points losses) to the battle rules to the siege rules as well. Do not apply the additional modifier for troop types not present in the opposing army.
Orbital Bombardment
Most relevant likely when playing out sieges using Epic, but potentially also relevant – if more dangerous – in other battles, an army with friendly ships in orbit over the battlefield, may be supported with orbital bombardment strikes. In the advance fire segment of the combat phase, a ship may place a barrage template anywhere on the battlefield. Roll to scatter, using the scatter and artillery dice. Orbital fire is notoriously inaccurate, so, even if a Hit symbol is rolled, still move the template a number of cm indicated by the artillery die in the direction of the small arrow integrated in the Hit symbol. After completing the scatter, repeat the process a second time. If a Misfire result is rolled at any time, there is some issue (e.g., the strike goes wieldy off target landing outside the battle area, the weapon systems fail. An orbital bombardment strike has 9 BP and a Target’s Save Modifier of -6.
Army Logistics and Reorganisation
At the end of a turn, armies can be reorganised, that means that within an army, cards can be shifted, split, or combined provided there are enough individual units, e.g., in an army containing a Leman Russ company card, this could be split into three Leman Russ support cards.
Reorganisations can also be carried out between armies in the same hex, or between a force and any armies in the same or an adjacent hex as the force.
Also at the end of a turn, any armies and forces on the map check their logistics. Supplies are measured and tracked in turns worth (i.e., weeks worth, months worth, or years worth) of supplies. Supplies can be carried in the logistics train of an army or can be stockpiled somewhere, such as within a fortress complex.
Reduce the available supplies of each army and each force by 1 point. If no supplies are available, i.e., there were 0 supply points when the deduction was called for, roll a D6 and consult the chart below.
| D6 | Effect |
| 1 | Lose D6x100 points of troops and army may not move next turn |
| 2 | Lose D6x50 points of troops and army may not move next turn |
| 3 | Lose D6x50 points of troops or army may not move next turn |
| 4 | Army may not move next turn |
| 5-6 | No effect |