[ghanja]

Or not even cast it if they already have it, though, breaking the invis would allow for a "fresh" cast, so whichever way you prefer:

sub EVENT_SPAWN {
	quest::settimer("portershout",90);
}

sub EVENT_TIMER {
	if($timer eq "portershout") {
		quest::stoptimer("portershout");
		quest::shout("Porting to all druid locations! Hail me near tunnel to Qeynos Hills!");
		quest::settimer("portershout", int(rand(100))+30);
	}
}

sub EVENT_SAY {
my %porthash = (
				"surefall" => ["Surefall Glade", 3, -391, -209, 4.75, 0],
				"butcher" => ["Butcherblock Mountains",68, 1984, -2135, 0],
				"feerrott" => ["The Feerrott",47, -1885, 367, 13.57, 0],
				"northkarana" => ["North Karana",13, -1494, -2706, -7.5, 0],
				"lavastorm" => ["Lavastorm Mountains",27, 460, 460, -84.88, 0],
				"misty" => ["Misty Thicket",33, -1896, -490, 120.34, 0],
				"sro" => ["South Ro",35, 317, -2034, -22.64, 0],
				"steamfont" => ["Steamfont Mountains",56, 1668, -1779, -108.07, 0],
				"commons" => ["West Commonlands", 21, 1427, 479, -51, 0],
				"toxxulia" => ["Toxxulia Forest", 56, -357, 1099, -57.93, 0],
				);
	if ($text=~/Hail/i) {
		plugin::Whisper("Hail! Where would you like to go? ");
		foreach my $key (keys %porthash) {
			$client->Message(315, "[".quest::saylink($key, 1, $porthash{$key}[0])."]");
		}
	}
	elsif (defined $porthash{$text}) {
		if ($client->IsGrouped()) {
			quest::doanim(43);
			foreach my $group_member (ClientCloseEnoughGroupMembers($client)) {
				$group_member->SpellEffect(43,10);
				if (!$group_member->FindBuff(34)) {
					$npc->SpellFinished(34, $group_member);
				}
			}
			castdelay(5);
			foreach my $group_member (ClientCloseEnoughGroupMembers($client)) {
				$group_member->Message (315, "".$npc->GetCleanName()." whispers, 'Off to ".$porthash{$text}[0]." you go!");
				$group_member->MovePC($porthash{$text}[1],$porthash{$text}[2],$porthash{$text}[3],$porthash{$text}[4],$porthash{$text}[5]);
			}
		}
		else {
			quest::doanim(43);
			$client->SpellEffect(43,10);
			castdelay(5);
			if (!$client->FindBuff(34)) {
				$npc->SpellFinished(34, $client);
			}
			quest::movepc($porthash{$text}[1],$porthash{$text}[2],$porthash{$text}[3],$porthash{$text}[4],$porthash{$text}[5]);
		}
	}
}

sub ClientCloseEnoughGroupMembers {
	my @return_group;
	my $entire_group = $entity_list->GetGroupByClient(shift);
	if ($entire_group) {
		for ($count = 0; $count < 6; $count++) {
			my $group_member = $entire_group->GetMember ($count);
			if ($group_member) {
				if ($group_member->IsClient()) {
					if ($group_member->CalculateDistance($x,$y,$z) <= 30) {
						push (@return_group, $group_member);
					}
				}
			}
		}
	return @return_group;
	}
}

sub castdelay{
	$delayOver = (time + $_[0]);
	while (time < $delayOver){}
	1;
}

Though, BreakInvis may also break invis to undead (which you may not care about in your case, but for those following along), I've never tested it against Invis vs Undead.

You can also use:

$client->BuffFadeBySpellID(43);

$group_member->BuffFadeBySpellID(43);