Hidden is a keyword ability in Shadow Era.

Hidden causes any hero or ally with the ability to become untargetable while hidden. In contrast to Stealth, this ability also protects from being targeted by ability cards and not just from attacks. Some cards also are able to hide attachments. This ability was introduced in Call of the Crystals. As of version 3.71 (September 2019), Hidden became a deprecated mechanic and was removed from cards it formerly appeared on.