First, You have to know which warp point you want to disable. Then use
disablenpc instance_npcname("warp name")
then add a trigger script to enable it.
base it here:
https://rathena.org/board/topic/92382-disable-warp-on-instance-dungeon/#entry243658
as an example:
prontera,150,150,0 script Instanced Prontera#a 101,{
set .@instance$, "Primer Jefe";
if (instance_id()) {
if (select("Enter Instance.:Cancel.") == 2) end;
if (instance_enter(.@instance$) != 0) {
mes "Instance entrance ^FF0000failed^000000.";
close;
}
} else {
if (select("Create Instance.:Cancel.") == 2) end;
if (instance_create(.@instance$) < 0) {
mes "Instance creation ^FF0000failed^000000.";
close;
}
mes "Instance created.";
close2;
instance_enter(.@instance$);
//this
.@map$ = instance_mapname("prontera");
.@label$ = instance_npcname(strnpcinfo(0))+"::OnMyMobDead";
monster .@map$,0,0,"--ja--",1002,150,.@label$,2;
//end
}
end;
//this
OnMyMobDead:
enablenpc instance_npcname("warppoint name");
end;
//end
OnInstanceInit:
disablenpc instance_npcname(strnpcinfo(0));
//this
disablenpc instance_npcname("warppoint name");
//end
end;
}