Use
DialogStartThreeSpeakerDialog("Dialog",CHARACTER_Char1,CHARACTER_Char2,_Player);
Their speaker number is the order they're listed. Meaning, Char1 is speaker 1, Char2 is speaker2 and the player would be speaker 3.
Add dialog as usual, and on each line set the "Speaker" for the NPCs, the players options should be set up as usual, with the "Owner" being set to #3.
Last edited by Burgee; 13/01/15 03:30 AM.