Crimson Cyst

Crimson Roots. The Crimson Cyst is rooted in place and thus constantly restrained. It cannot move but can still take actions.

Infectious Growth. When an infected creature dies, up to four (1d4) new cysts form within seconds. The newly formed cysts use the remains as nutrients, spreading a fleshy mass in a 5-foot radius around the corpse. This new cysts have half the hit points of a normal crimson cyst and can mature into a full crimson cyst after 24 hours. After 72 hours the Crimson Cyst evolves into a Crimson Plague Cyst.

Spore Burst. When the crimson cyst is reduced to 0 hit points, it releases a cloud of spores in a 10-foot radius. Each creature in that area must succeed on a DC 10 Constitution saving throw or be poisoned for 1 minute. While poisoned in this way, the creature suffers 1d2 poison damage at the start of its turn. A poisoned creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If the creature is still poisened, each new bursts of a Crimson Cyst will increase the DC Constitution saving throw by 1 (e.g, two cysts bursts and affect one creature. The second burst after the intitial will increase the DC by 1 making it 11)

(Note: If the Crimson Cyst is destroyed by fire damage, it will not release any spores)

Crimson Spread. At the start of each of the crimson cyst's turn, it spreads a fleshy mass in a 5-foot radius around it. Each turn after the initial turn increases the size of the infected area by a 5-foot radius to a maximum of a 10-foot radius per Crimson Cyst. Any creature that starts its turn within this infected area must succeed on a DC 10 Constitution saving throw or take 1d2 necrotic damage. The infected area remains hazardous for 1 minute, after the Crimson Cyst is destroyed.

 (Note: The infected area can be destroyed with fire. Any fire damage will suffice.)

Voluntary Burst. When a creature is within 10 feet of the cyst, it can use its action to make a Wisdom (Perception) check with a DC of 10. If it succeeds, it rapidly shakes and bursts open, reducing its hit points to 0, activating Spore Burst.