Quiet enough that only Rian can hear it (he's closer, and his own bulk absorbs much of the sound, the voice whispers from deep inside the tunnel,
"I can hardly bear the suspense...c'mere, big boy, lemme run my fingers through your hair." Quite in spite of himself, the paladin finds the words physically exciting (in a shiver-down-the-spine sort of way, to be perfectly clear). His mind might consider the extremely personal entreaty more than a little creepy, but on a gut level, he experiences a profound urge to follow the summons.
Kast spots something down the tunnel to the right which catches his attention.
As he announces resolve to pick a tunnel at random, Vualn feels himself drawn, as if by serendipity, toward the tunnel on the left.
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Each of you gimme a Will save.