Complex sentence: It is eventually determined that the substance composing the meteor is susceptible to water: if wetted, it grows into black, crystal-like shafts which absorb all available liquid nearby, including from any animals or humans who come in contact with it.
Split into simpler sentences: It is eventually determined that the substance composing the meteor is susceptible to water. If wetted it grows into black, crystal-like shafts which absorb all available liquid nearby, including from any animals or humans who come in contact with it.