Unlike your common unilateral falling block games, 'Double Cross' implements a bidirectional paradigm expanding the genre in both dimension and difficulty.
Blocks fall from the top and fly in from the side settling in a joined "play area". Deletions occur when rows of ten blocks are completed. A horizontal row of 10 will cause the blocks to fall down, and a vertical row of 10 will cause the blocks to "fall" to the right. If a vertical row is completed during a vertical drop or a horizontal row is completed during a horizontal drop the corresponding deletion will not occur until the next turn. This can and will lead to non-intuitive results. Focus on the vertical alone and you will die from horizontal negligence and vice versa.