need help for spawning boss and timed proximity action npc

[quakeman00]

anthell02,41,258,4	script	Egg Reaction	557,1,8,{
	end;

OnTouch:
	if (countitem(574) > 0){
			mes "Our Precious Eggs!";
			next;
			delitem 574,1;
			hideonnpc "Egg Reaction";
			close;
		}
	else {
			}
close;            
}

what im looking to do here is make the npc ract when the player is holding an egg , but if the npc react , it will disable itself for 15 minutes. when the npc react , it will spawn a maya purple and removing an egg from the player's inventory and being unresponsive for 15 minutes. when the 15 minute timer end , the maya purple vanish "or die whitout droping any loot" i dont know which or how. this is what ive managed to figure for myself but hiding the npc dosent stop it from reacting. also if its posible to spawn the maya purple AFTER the window is closed so it dosent kill the players who brought the egg

Edited March 3, 2017 by quakeman00