

THIS MOD REQUIRES GECKOLIB
This mod adds an infection to Minecraft. It will start as mobs which will assimilate almost any other mob, sometimes these creatures can evolve into much more powerful mobs known as "Primitive Advanced Parasites" they are much larger and will see from a long distance away.
When a parasite dies it has a small chance to place a growing hivemind beneath it, this block will wait a few seconds before becoming a primitive hivemind. This is the beginning of the main infection, the hivemind will place tumors next to it which will spawn little mites that change every block beneath it into an assimialted version. (EG: stone becomes "primitive phayrium") These blocks will then spread slowly to nearby blocks, they can also grow some parasitic plants above or below them.
These blocks can sometimes mutate into other blocks like tumors, sentries, and pit plants. Sentries will spawn assimilated mobs above them when a player is nearby, and pit plants look similar to assimilated dirt (primitive phayrilesh) and will melt you and your armor when you fall into one, they can also become a consumer. A consumer will eat any assimilated mob that falls into it, after it eats 3 of them it spawns a primitive advanced parasite above it and becomes a pit plant once again.
After a while tumors and sentries will go dormant and spawn either a hivewarden or beacon above it, both of these mobs are classified as plants, and they will spawn basic parasites when you are nearby. The beacon can evolve to stage 2 (and stage 3 in the latest beta) which is much stronger and will attack you if you get to close.
There is a lot more to this mod that i haven't talked about like armor and items, but that was most of the important stuff, so have fun! (and suffer)
"Jade" "J.E.I." and "Neat" recommended.
note: the images are from the latest beta