skeleton wrote:If your Army Faction is T’au Empire, then in your Shooting phase units from your army can work in pairs to help each other target specific enemy units.
When they do this, one unit is the Observer unit and the other is their Guided unit. The enemy they are targeting is called their Spotted unit.
Each time you select this unit to shoot, if it is not an Observer unit, it can use this ability. If it does, select one other friendly unit with this ability that is also
eligible to shoot (excluding Fortification, Battleshocked and Observer units). Until the end of
the phase, this unit is considered a Guided unit, and that friendly unit is considered an Observer unit. Then select one enemy unit that is visible to both your units to be their
Spotted unit.
Until the end of the phase:
■ Each time a model in a Guided unit makes
an attack that targets their Spotted unit,
improve the Ballistic Skill characteristic of
the attack by 1 and, if their Observer unit
has the Markerlight keyword, the attack
has the [IGNORES COVER] ability.
■ Each time a model in a Guided unit makes an
attack that does not target their Spotted unit,
worsen the Ballistic Skill characteristic of the attack
Thats whats in the codex/index
If i read this correct, it doesnt matter where the units are, solong as the can see the target unit.