I have a dungeon boss that does something very similar to this, I used scripting and dialog to complete this.
If you are wanting the MOB to chat, summon, chat some more, summon again, chat, etc. you can easily do this with the dialog, and it will solve your problems pretty cleanly. To address the characters in the party, you do this as you would in any normal dialog (interjections, etc.) and have the actions at the end of each tree summon your monsters to specific locations. Once the monsters (via death variable) are dead, have the conversation start again. This will give you your classic 'monologue' of evil-doer in between waves of henchmen.
Here is what I have, though the area script is not here, it fires the incremental dialogs:
BEGIN MISTIM
IF ~True()Global("Mistimore","GLOBAL",0)~
THEN BEGIN A_0
SAY ~Ahhh. A mortal has entered my domain. I thought I heard the moans of my children.~ [UNEARM01]
= ~You have come all this way for naught, <PRO_RACE>, you will become one of my children soon.~
= ~Let us begin our dangerous game.~
IF ~~ THEN DO ~SetGlobal("Mistimore","GLOBAL",1)CreateCreature("decmist",[646.428],0)CreateCreature("decmist",[502.483],14)CreateCreature("decmist",[440.562],12)CreateCreature("decmist",[498.653],10)~ EXIT
END
IF ~True()Global("Mistimore","GLOBAL",1)~
THEN BEGIN A_1
SAY ~So, you think you can get the better of me then? These puppets are fodder, but let me get my ammusement from them.~ [UNEARM02]
= ~You will die here yet, <CHARNAME>.~
IF ~~ THEN DO ~SetGlobal("Mistimore","GLOBAL",2)CreateCreature("decmis2",[646.428],0)CreateCreature("decmis2",[502.483],14)CreateCreature("decmis2",[440.562],12)CreateCreature("decmis2",[498.653],10)~ EXIT
END
IF ~True()Global("Mistimore","GLOBAL",2)~
THEN BEGIN A_2
SAY ~Very well, if you wish to be a poor sport about it, then I will deal with you myself.~ [UNEARM03]
= ~Die, fool, and may your bones walk these halls for eternity!~
IF ~~ THEN DO ~SetGlobal("Mistimore","GLOBAL",3)Enemy()ForceSpell([PC],BEHOLDER_CAUSE_SERIOUS_WOUNDS)Attack(PLAYER1)~ EXIT
END
Hope this is what you were asking about, I could be off topic entirely.
Sticz
"For a crazy person, you don't drool much." Complement from Dilbert's Wally.