But honestly, I think it will be easier to script like this:
prontera,155,180,3 script Popo 1031,{
areamonster "prontera",150,175,160,185,"Poporing",1031,10,"Popo::OnWrongKill";
areamonster "prontera",150,175,160,185,"Poporing",1031,1,"Popo::OnRightKill";
npctalk "Find the correct Poporing to receive the reward!";
end;
OnWrongKill:
areamonster "prontera",150,175,160,185,"Poporing",1031,1,"Popo::OnWrongKill";
atcommand "@die";
dispbottom "You kill the wrong Poporing!";
end;
OnRightKill:
killmonster "prontera","Popo::OnWrongKill",1031;
announce strcharinfo(0)+" has killed the right Poporing!",0;
getitem 501,1;
end;
}