The Hallucination Torva Helm is a part of the Hallucination Torva Set. You can get the set from the Donation Point Store at home. The helm, like the rest of the set, is purely cosmetic and has no stats.
At the moment, the price of Hallucination Torva Helm is roughly: 50k-100k DScoins
Currently, it is not dropped by any bosses.
It cannot be obtained from any boxes or chests.