As a bonus action, the strobing fungus can start emitting a powerful, strobing light. It rapidly alternates between shedding bright light in a 60-foot radius and shedding no light, creating a dizzying effect unless the area’s ambient light is bright light. Each creature within 60 feet of the strobing fungus and that can see the light must succeed on a DC 14 Constitution saving throw or be blinded for 1 minute. A blinded creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Unless surprised, a creature with a shield or other similarly-sized object can use its reaction to raise the object and protect its eyes from the light, avoiding the saving throw. If it does so, it can’t use that object for anything else. For example, a creature using a shield to protect its eyes loses the shield’s bonus to its Armor Class while using the shield in this way. If the creature looks at the strobing fungus or lowers or uses the object protecting its eyes, it must immediately make the save.

While emitting light, the strobing fungus can’t attack. It can stop emitting light at any time (no action required).