Welcome to the Choose Your Own Error Adventure. This was imported from an old database that many people contributed to, and as such has some errors and sections of bad writing. If you come across these, feel free to leave a comment on the entry and an Elite Councilmember will be along to fix it... eventually.
You encounter a level 3 error.
It is a mass of color and pattern completely alien to the world. You know it for what it is: A loose thread in the fabric of reality, one that will corrupt anything it touches. If allowed to grow unchecked it could eventually consume everything. Thankfully this one is only a level 3 error, and as such is only a few feet across.
You didn't see it until you were nearly on top of it, thanks to a bend and small rise in the path you were walking. It's now within attacking distance, so you must make your choice quickly.