Chimerical

From the White Wolf Wiki, the most complete White Wolf reference

Chimerical reality, unlike the mundane, is forged by whim and fancy. Much like the Dream Spirits and Epiphlings of the shifters and mages, much of the world's chimerae (chimerical beings and objects) are formed by the hopes and fears, dreams and nightmares, delusions and illusions of all sentient beings.

Formed of glamour (considered by mages to be a form of quintessence, much like diamonds are a form of carbon), chimerial reality is generally invisible to most beings. Being Enchanted by glamour or having fae-sight can allow one to see and often interact with the chimerical world.