I like the sleeping people are actively NOT listening therefore they could be determined as rolling a 0 on their listen check. With that in mind, I would resolve this as -10 to listen checks. I like to allow my players to roll whenever possible therefore to help interpret the die roll into the concept of ROLLING a 0, I simply give them -10 assuming an average roll on d20 is a 10.
To help make it easy, just remember to use the difference of altering a DC and adding or subtracting circumstance bonuses.
The sounds of battle or "level" of noise could alter the base DC.
The fact of them sleeping and/or what state of sleep they are in (if you go into that much detail) would alter the circ bonus you add or subtract to their roll.
To summarize a good rule could be something like..
DC 5 - Sounds of battle in the camp.
+1 DC for every 10ft the battle is AWAY from the camp.
Have the player(s) sleeping roll the listen check.
ADD a circumstance modifier of -10 to their roll.
Use the listen check skill DCs as per the skill listing as a good baseline to establish a base DC for whatever the noise level is.
I have found it helps tremendously when learning to seperate and differentiate when I mess with DCs and when I leave them alone and just alter the rolls with circ bonuses (+ or - )
To help make it easy, just remember to use the difference of altering a DC and adding or subtracting circumstance bonuses.
The sounds of battle or "level" of noise could alter the base DC.
The fact of them sleeping and/or what state of sleep they are in (if you go into that much detail) would alter the circ bonus you add or subtract to their roll.
To summarize a good rule could be something like..
DC 5 - Sounds of battle in the camp.
+1 DC for every 10ft the battle is AWAY from the camp.
Have the player(s) sleeping roll the listen check.
ADD a circumstance modifier of -10 to their roll.
Use the listen check skill DCs as per the skill listing as a good baseline to establish a base DC for whatever the noise level is.
I have found it helps tremendously when learning to seperate and differentiate when I mess with DCs and when I leave them alone and just alter the rolls with circ bonuses (+ or - )