ViruXine.W32 virus hides their presence by changing the underlying executable code. This Virus code mutates while keeping the original algorithm intact, the code changes itself each time it runs, but

A polymorphic virus changes its observable binary signature each time it replicates or runs, typically through variable encryption keys or code obfuscation routines. However, the core payload algorithm and semantics remain completely unchanged - only the appearance of the code changes. This matches the described behavior precisely: code that mutates on each execution while the original function stays intact.

A metamorphic virus goes further than polymorphism by completely rewriting its own code logic and structure each iteration, potentially altering the algorithm itself rather than just changing an encrypted wrapper.

Dravidic Virus is not a recognized malware classification in any standard security taxonomy and does not describe any documented virus behavior.

A stealth virus hides its presence by intercepting OS system calls to conceal file size or timestamp changes, not by mutating its own executable code each run.