The following is an excerpt from page 114 of the Warhammer Chronicles 2004 release with an expanded explanation regarding Unit Strength and Single Model's Movement.
The Warhammer rulebook and a series of articles in White Dwarf have tried to clarify different Unit Strengths and the many subtle ways in which different single models relate to the Movement rules when they are moving on their own. Where models are ranked into units, they follow the normal rules for unit movement given in the Warhammer rulebook, except for skirmishers and fast cavalry which follow the rules detailed in their own sections.
The following chart and the notes below are the Warhammer team's last and final decision on such matters. They officially replace everything else that has been said on it and, we hope, will settle all discussions and become a most useful gaming aid.
Model Type | Movement | Unit Strength |
Roughly man-sized. Square 20/25 mm base. On foot. | As skirmishers | 1 |
Up to & including Ogre-sized.* Square 40/50 mm base. On foot. | As monsters | 3 |
Monster (larger than Ogre-sized).** Any base/no base. | As monsters | Starting Wounds |
Cavalry.*** 25 x 50 mm base. | As monsters | 2 |
Chariots. | As monsters (no marching) | 4 |
Ridden monsters/chariots. | As monsters/chariots | As monster/chariot +1 |
Move as Monsters: No need to turn or wheel - can pivot on the spot with no penalty but behave like units in all other respects (90° arc of sight, pay penalties for difficult terrain/obstacles, cannot march if within 8" of enemies at the beginning of the turn and may not turn if charged in the flanks or rear).
Move as Skirmishers: No need to turn or wheel, can pivot on the spot with no penalty, 360° arc of sight for charges, etc, no penalties for difficult terrain/obstacles, can march even if within 8" of enemies at the beginning of the turn, will line up to formed units charging them and not vice versa, & don't have front/flanks/rear until engaged in close combat.
Units of Flyers: Always count as skirmishers and always have a Unit Strength of 1 per model, regardless of size, wounds, etc. Can't fly in woods even if they move as skirmishers. Single flying models follow the rules for their type in the chart.
War Machines: Have a Unit Strength equal to the number of crew left. Move as skirmishers, with the exceptions noted in their rules.
* Includes Swarms, Chaos Spawn, etc.
** Includes Pegasi, Stegadon, Giants, etc.
*** Includes Flesh Hounds, Dire Wolves, Chaos Hounds, etc.