Indigo Blight
Indigo Blight has evolved from its ancestor to become a scourge to the crystal flora. It can exist as clouds of free swimming cells which photosynthesize, but it can also parasitize crystal flora. Sunlight zone, sessile crystal flora are the only crystal flora at risk, as the Indigo Blight still requires sunlight, and has struggled to spread and establish themselves inside free floating crystal flora. At the start of an attack, they will congregate on the crystal surfaces and secrete enzymes that will eat away at the crystal through any weak points in the shell. Once a crack is made or found the Indigo Blight will rush in and start feeding on the crystal flora's innards. They will replicate rapidly and eventually hollow out the crystal. From then on they will continue to propagate and disperse from the crystal husk to feed on more crystals as time goes on. Well established Indigo Blight will sometimes release small bubbles of many cells to drift to a new crystal, giving the infection a large starting population to overwhelm the crystal. Crystal flora afflicted with the blight will have blue patches on their surface and a bluish tint underneath the shell where it has infiltrated. To deal with primitive immune systems like that of the Sea Rupees, Indigo Blight have developed a countermeasure. They will continue to produce the dissolving enzymes to weaken the mineral tags that the Sea Rupees use to identify foreign cells. By removing the mineral tags in an effected area, the Rupees own immune system will attack both the Indigo Blight and the Rupees body cells. This will create a standstill in which the Indigo Blight is destroying the Sea Rupees detection system, and the Rupee is attacking the enemy and itself. If the Sea Rupee damages itself significantly, along with the damage from the Indigo Blight itself, its efforts will weaken and the Indigo Blight may take over. The struggle will result in a more degraded crystal shell for the Indigo Blight to base future attacks from.