question about cover/concealment

[davschm]

What do you call it when a person wants to fire into melee with a ranged weapon / ray spell.

Sometimes a caster in my group will stand beside two melee fighters and try to attack the enemy one with a ranged attack. He has unobstructed line of site to the square, but they are in combat currently. What is the penility? And is one of them considered to be in cover or concealment (whats the difference)?

Fighter
- | ----------------------- Caster
Orc

Would it make a difference if the caster was behind his ally and that ally was face to face with an enemy?

Caster ----------------- Fighter - Orc

Is the fighter now giving extra protection to the Orc, or is it the same as if the caster was at a 90 degree angle from the conflict? If the caster did shot, is there a risk to the fighter?

 

[Maidhc O Casain]

The attacker takes a -4 penalty to his/her attack roll in order to avoid the chance of hitting an ally.

 

[GlassEye]

Unless the caster has the Precise Shot feat he'll take a -4 to hit the orc for firing into melee. In your second scenario, the orc also has soft cover from the fighter since the fighter is between the caster and the orc and gains a +4 to his armor class. There is no risk that the fighter will get hit with the caster's ray.

As far as I understand, cover is when something (or someone) blocks or partially blocks the line of effect between the ranged user and his target.

Concealment is very similar but the target is obscured somehow such as by darkness. It provides a chance to miss.

 

[Azmyth]

What do you call it when a person wants to fire into melee with a ranged weapon / ray spell.

The term is 'soft cover'.

As previously stated, -4 penalty to ranged attacks firing through soft cover.
In your other example, a -4 penalty for firing into melee is applied if the shooter does not have the Precise Shot feat.
If your target is large enough that part of it is at least 10' from a friendly, you can avoid the -4 penalty by aiming away.
If your target is 2 size categories larger that the friendlies it is engaged with, the penalty is reduced to -2. Three sides larger has no penalty.
These penalties can combine in some combat situations.

If the caster did shot, is there a risk to the fighter?

Nope. No RAW fumble or miss fire rules, but I know loads of GMs that houserule this.