Monster Blood IV is a novella written by R. L. Stine. It was first published in 1997 and is the 62nd book in the original Goosebumps book series.
Description[]
It's Four Times As Evil!
Evan Ross can't forget about Monster Blood -- the evil green slime that never stops growing. It can turn ordinary pets into ferocious animals and twelve-year-old kids into freakish giants.
But now there's a new kind of Monster Blood in town. It comes in a can just like the others. Only difference is this slime is blue instead of green. And instead of just growing, it's multiplying -- into terrifying blue creatures with razor-sharp teeth...