See the creep it is pointing at. It doesn't do damage per se but once it is joined to a few more turrets it can do more useful things. For example, drop a Targeter somewhere, select it and press J to start the joining process:
The red line tells you which targeter you're joining to. Move the red circle over the turret you wish to join to and it'll go green:
Finally click on that turret to join it to the Targeter. Any joined turrets are indicated by a line between the Targeter and the turret, shown when the Targeter is selected:
Quite sweet really. Then, when anything comes in range of the Targeter it will call in fire support from the linked turrets. You can join up to three turrets to any Targeter, joining any more will un-join the first one you joined. To un-join a turret, press J and click on that turret again.
Possible applications include linking to a remote combo cluster:
Which will cause the blue combo to fire when anything enters the range of the Targeter.
The next new feature is the directional targeting, which is available on any turret. Select a turret and press D to cycle through the directional targeting modes; wide, medium, narrow or full. When changing modes the angle will be set pointing towards the mouse cursor. To alter the angle without changing the targeting mode press Shift-D. This sets the angle to point at the cursor without changing the targeting mode:
Note the cluster bomb in mid-flight. The green arc is the normal weapon range, the white part is the extended range from a Ranger turret that is just out of shot.
So to summarise:
- Targeter turret, press J to join it to up to three other turrets by clicking on them.
- Directional targeting, press D to cycle through the modes, Shift-D to set the angle