Hi guys! When u have s craracther using stealth. And an other one behind him. Can oposites target the behind one? Since that the hidden one its not see?

Can u roll to break away and use charge or running shot?

1.) no

2.) yes. if you fail the roll, the action is resolved immediately.

....meaning the victim of the failed Breakaway Roll can do nothing except take an Action Token, no Attack may be made.

Oks. I get it Now. Pulse wave can make damage across characters? Lets say. One behind the other and the range of pulse wave reachs both

Yes. Pulsewave says, "Give this character a ranged combat action even if it is adjacent to an opposing character; the area of effect for this attack is half the character’s range value. Draw lines of fire to all other characters within the area of effect, including at least one opposing character; these lines of fire ignore all game effects except for walls, blocking and elevated terrain..."
So by "ignor[ing] all game effects," that also includes figures... you could have a line of several characters in a straight line and as long as they were all in that area of effect, they would all get hit and none would block the other.

Great thanks! The roll for pulse wave is: 1 roll against every defensa right? Those ones doesnt hit does not take damage?

Correct!!!!

Note that this includes friendly characters as well as enemies.

Yes of course. Thanks