On the overland map, a unit with Forester pays no more than 1 Movement Point when moving into a Forest tile. When the unit is part of a stack, the entire stack pays no more than 1 Movement Point when moving into a Forest tiles. This allows stacks led by a Forester unit to quickly cross heavily-wooded terrain.
There is no known method of adding Forester to a unit that does not possess it by default, whether by spells or through Magical Items. Of course, the Pathfinding ability, which can be added to any unit, is superior to Forester in every way.
Intelligent creatures will normally adapt to their surroundings, especially over many generations. Some cultures specialize in survival in heavily-wooded terrain, learning to find paths through the undergrowth, track animals worthy for consumption, find water sources and so on. They can then lead entire armies through such terrain, easily.
High Elves are exceptionally good at this, having honed their skills to be more in-tune with the forests and their creatures. Animals that live predominantly in forests also develop this ability.
When a Walking unit with Forester is moving across the overland map, it can enter any Forest tile at a cost of only 1 Movement Point. Normally, Walking units would pay 2 Movement Points to enter Forest tiles.
Forester applies only on the overland map. Units possessing Forester do not behave any differently from other units when fighting in Forest tiles.
Group Forester Movement Edit
A Forester unit traveling as part of an army will bestow the aforementioned effect on all units stacked with it. As a result, the entire stack will pay only 1 Movement Point to enter any Forest tile.
Note that if the stack contains only Flying units, the Forester ability has no effect: the stack will pay only 1 Movement Point to enter any tile, as is normal for Flying units. However, if the stack contains at least one Walking unit, the movement costs described above are in effect. It does not matter which unit in the stack possesses Forester.
It should also be noted that when a Forester unit is traveling as part of an army and there is another unit with the Mountaineer ability in that same stack, the entire stack will travel using the Pathfinding ability (see the Pathfinding article for more information).
Units with Default Forester Edit
There are no fewer than 12 units in the game that possess Forester by default. More than half of these are Normal Units from the High Elf race, 2 are Fantastic Creatures from the Nature Realm, and 2 are Heroes.
Note that the majority of these units are Walking units by default (thus enjoying the benefits of the Forester ability, as explained above). The two Heroes arguably benefit much more from Forester, as Heroes' Movement Allowance can easily be increased with the use of Magical Items - allowing them to cross vast distances rather quickly if ample forested terrain is present.
The Sprites are the only Flying units on this list. This means that, while alone, they feel no benefit from Forester. However, whenever they are in a stack containing at least one Walking unit, the Forester ability kicks in and will speed up the movement of the stack.
Acquiring Forester Edit
There is no known method in the game to add Forester to a unit that does not possess it by default.