An enemy must be a legal target for an attack, special ability, or Force power. The acting character must have line of sight to it. An enemy with cover is not a legal target unless it is the nearest. If one or more enemies are adjacent to the character, only those enemies are legal targets."
Can someone explain it better? For example, Blaster barrage says I can attack every legal target once. Are characters with no cover, legal targets?
Yes, they are.
To determine legal targets:
* If any enemy is adjacent, only adjacent enemies are legal targets.
* Otherwise, the nearest enemy is a legal target. Also, any enemy without cover is a legal target. If two enemies happen to be the exact same distance away they both count as 'nearest' and are legal targets even if they have cover.
(Note that abilities like Stealth and Cloaked and Accurate Shot get around the targeting rules in various ways.)