try this
prontera,155,181,4 script Portal 45,2,2,{
OnTouch:
if( .Event ) warp "guild_vs5",0,0;
end;
OnMinute00:
set .Event,1;
hideoffnpc strnpcinfo(0);
announce "Loot event has started. Rush to the Portal.",0;
sleep ( 30 * 1000 ); // How long Portal Open ?
announce "Portal will be close by now..",0;
hideonnpc strnpcinfo(0);
set .Event,0;
monster "guild_vs5",0,0,"Name",1002,30,strnpcinfo(0)+"::OnMobKilled";
sleep ( 60 * 1000 ); // Last how long the Event ?
killmonster "guild_vs5","All";
mapwarp "guild_vs5","prontera",155,181;
end;
OnMobKilled:
monster "guild_vs5",0,0,"Name",1002,1,strnpcinfo(0)+"::OnMobKilled";
end;
}