It is a phrase that represents a collision of casual gaming, digital rebellion, and the endless cat-and-mouse game between system administrators and bored internet users.
To understand the demand for the "unblocked" version, you have to understand the psychology of the game itself. Block Blast is a variation of the block puzzle genre (think Tetris meets Sudoku). You drag shapes onto a grid, clearing lines to score points. It requires just enough strategy to feel satisfying, but little enough to be mindless. blockblast unblocked