An ear-piercing shriek echoes in the cavern. The sound comes from a human-sized mushroom whose stalk steadily swells with air as it shrieks.
Thunderous Shriek. Boomers are a subspecies of shrieker, nearly indistinguishable from their more innocuous cousins. When shrieking, however, the stalk of the boomer noticeably expands, swelling with air until it releases the air in a thunderous burst of noise. Like its more common relative, it is often deliberately cultivated by intelligent subterranean races as a defensive measure against intruders.
Boomer
Medium plant, unalignedArmor Class 7 (natural armor)
Hit Points 22 (4d8 + 4)
Speed 0 ft.
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 1 (-5) | 1 (-5) | 12 (+1) | 1 (-5) | 3 (-4) | 1 (-5) |
Damage Immunities thunder
Condition Immunities blinded, deafened, frightened
Senses blindsight 30 ft. (blind beyond this radius), passive Perception 6
Languages —
Challenge 1/2 (100 XP)
Deafening Boom. When a creature hits the boomer with a melee attack, the boomer releases a blast of sound. Each creature within 10 feet of the boomer that can hear it must make a DC 12 Constitution saving throw. On a failure, a creature takes 5 (2d4) thunder damage and is incapacitated until the end of its next turn. On a success, a creature takes half the damage and isn’t incapacitated.
Death Burst. When it dies, the boomer explodes in a cacophonous burst. Each creature within 30 feet of the boomer that can hear it must make a DC 12 Constitution saving throw. On a failure, a creature takes 7 (2d6) thunder damage and is deafened for 1 minute. On a success, a creature takes half the damage and isn’t deafened.
False Appearance. While the boomer remains motionless, it is indistinguishable from an ordinary fungus.
Reactions
Shriek. If bright light or a creature is within 30 feet of the boomer, it emits a shriek audible within 300 feet of it. The boomer continues to shriek until the disturbance moves out of range and for 1d4 of the boomer’s turns afterward.