This is a very dangerous memory resident parasitic virus. It hooks INT10h and 21h, and writes itself to the end of EXE files that are executed or opened. Depending on the system date and their counters, the virus "shifts" the screen.
It also hooks INT 13h, and starting from 10th of each month, corrupts some files while writing to them. On the same days, this virus also writes a Trojan program to the end of infected EXE files instead of infecting them. When executed, this program erases the hard drive sectors.
