Veil

The veil spell enables the wizard to instantly change the appearance of his surroundings and party or create hallucinatory terrain so as to fool even the most clever creatures (unless they have the true seeing spell, a gem of seeing, or a similar magical aid). The veil can make a sumptuous room seem like a filthy den; even tactile impressions conform to the visual illusion. Likewise, a party might be made to resemble a mixed band of brownies, pixies, and faeries led by a treant. If hallucinatory terrain is created, touch does not cause it to vanish.