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Ironrot Lichen

Ironrot Lichen CR 7

The patch of rust stirs, exposing plant-like tendrils that extend towards you.

XP 3,200
N Small plant
Init +5; Senses blindsense (vibration) 60 ft., low-light vision; Perception +14


EAC 19; KAC 21
Fort +11, Ref +9, Will +6 Immune cold, plant immunities, vacuum


Speed 10 ft., climb 10 ft.
Melee tentacle +17 (1d10+9 A plus ironrot)
Space 5 ft.; Reach 10 ft.
Offensive Abilities spore cloud (usable every 1d4 rounds)


Str +2, Dex +5, Con +4, Int —, Wis +0, Cha +0
Skills Athletics +19
Other Abilities mindless


Ironrot (Ex)

The corrosive touch of ironrot lichen is devastating most technological items. When the lichen hits with a tentacle attack, the victim must attempt a DC 15 Reflex save or it corrodes an item of up to five bulk they are carrying.

The corroded item drops to half hit points and immediately gains the broken condition. A broken item touched is seized by rust, being reduced to 1 hit point and rendered unusable until repaired.

Being mindless, the lichen will generally go after the highest bulk item it can first.

Spore Cloud (Ex)

Every 1d4 turns, ironrot lichen can expel a cloud of spores, exposing all living creatures within 10 feet to the Ironrot Plague.

Ironrot Lichen Ironrot Plague

Type disease (inhaled); Save Fortitude DC 15; Track physical; Frequency 1/day

Effect Whenever an infected creature fails a saving throw against the disease, a random technological item they’re carrying is affected as though they failed a save against the Ironrot ability. When the infected creature reaches the dead condition, their corpse sprouts a fresh patch of ironrot lichen.

Cure 2 consecutive saves


Environment any non-aquatic
Organization solitary, pair, or carpet (3–8)

Ironrot lichens faced extermination in most inhabited areas after infestations of the plant wiped out armor, tools, and weapons, while spreading from settlement to settlement on tainted metal.

The hardy plants went into a long dormancy in hidden areas and have thus far avoided complete destruction. Ironrot lichens can enter a long-term stasis, and they reawaken after many locations have forgotten about the massive damage they cause. They also thrive in extreme environments where they could reproduce through red-blooded creatures populating those environments. Patches of dormant ironrot lichen have also spread to airless locations in space, becoming a menace to miners who rely on metal tools and habitats on the asteroids they work. A patch of lichen takes up a roughly 3-foot-diameter space and is virtually weightless.

Section 15: Copyright Notice

Alien Bestiary (Starfinder) © 2018, Legendary Games; Lead Designer: Jason Nelson. Authors: Anthony Adam, Kate Baker, John Bennet, Eytan Bernstein, Robert Brookes, Russ Brown, Duan Byrd, Jeff Dahl, Robyn Fields, Joel Flank, Matt Goodall, Robert J. Grady, Jim Groves, Steven T. Helt, Thurston Hillman, Tim Hitchcock, Nick Hite, Daniel Hunt, Mike Kimmel Marshall, Isabelle Lee, Jeff Lee, Lyz Liddell, Jason Nelson, Richard Pett, Tom Phillips, Alistair J. Rigg, Alex Riggs, Wendall Roy, Mike Shel, Neil Spicer, Todd Stewart, Russ Taylor, Rachel Ventura, Mike Welham, George Loki Williams, Scott Young.