kanithardm said:
When does combat technically start? If the enemy is behind the door and you know it can you ready actions? I always allowed it, but everyone seems to disagree. For example, the rogue snuck ahead and spotted a goblin patrol without being seen. He ran back to the party and the all readied actions for when the goblins came. I counted them as not flat-footed and aware as long as the goblins came through the entrance they were guarding. Is this okay?
I second that the best place to look is the DMG, and analyze those rules.
When I start combat is tricky to put it into words.
I'll give an example.
A, B and C is one group of combatants.
X, Y and Z are the other group of combatants.
A detects the presence of X and Y.
A goes back to inform B, but makes a slight sound, heard by X.
X doesn't treat the sound as a danger, although he does investigate it.
X doesn't see anything.
A informs B, but B, hasn't detected the presence of foes yet.
A and B wait.
Y approaches. And is heard only by A.
Y appears and now A and B see Y. Although B didn't heard him, now he sees Y.
Y doesn;t see A and B.
B in his anxiety, attacks yells. A wasn't prepared for this. B didn't coordinate, nor he made it obvious what actions he would take.
Y hears B, and considers it a threat.
Combat started, and the surprise round was B yelling.
Now everyone rolls initiative and each combatant is flat footed until they act.