What was the name of the rat that almost killed Buratino? - briefly
The rat that nearly killed Buratino is named Misha.
What was the name of the rat that almost killed Buratino? - in detail
The antagonist rodent in Alexei Tolstoy’s “The Golden Key, or the Adventures of Buratino” is identified only as the Rat. In the original narrative the creature has no personal name; he is consistently referred to as “the Rat” (Russian: Крыса). Some later adaptations assign him the transliterated name “Krysa,” but the source text leaves him nameless, using the generic term to emphasize his role as a threatening animal rather than a distinct character. Consequently, the answer to the inquiry is that the rat is simply called “the Rat,” occasionally rendered as “Krysa” in derivative versions.