X Rock is sort of a mixture between Tetris and Columns. Cross-shaped pieces consisting of five balls of various colors drift down. The pieces can be rotated with the space bar, which sometimes changes the color of the center ball, and of course moved left or right. Two balls of the same color that touch will vanish. Diagonals don't count, after all the balls don't touch there.
Unlike most Tetris-style games, does not become faster as you level up. Instead, the rules become more difficult. From level 2 on, ivory balls will vanish only if there are three in a row. On the right side of the screen there is a picture that slowly gets uncovered. Once it is fully visible, the level is finished and the picture is displayed full-screen. I suppose these pictures get more erotic with the higher levels, but I never got very far.
There are two executables in the archive, VXROCK.EXE for VGA, HXROCK.EXE for Hercules. In DOSBox, the former tends to crash after the title screen unless the CPU cycles are cranked up high enough, the latter tends to crash in any case. I have not tested it with a real Hercules card.
