We prove that the 2017 puzzle game ZHED is NP-complete, even with just 1 tiles. Such a puzzle is defined by a set of unit-square 1 tiles in a square grid, and a target square of the grid. A move consists of selecting an unselected 1 tile and then filling the next unfilled square in a chosen direction from that tile (similar to Tipover and Cross Purposes). We prove NP-completeness of deciding whether the target square can be filled, by a reduction from rectilinear planar monotone 3SAT.

翻译：我们证明2017年的拼图游戏 ZHED 是NP 完成的, 即使只有一张牌。 这种拼图是由一组单位方格 1 瓦和网格的目标方块来定义的。 移动包括选择一个未选中的 1 瓦, 然后从该瓷砖( 类似于 Tipover and Cross Ocsuritys) 中选择一个方向填充下一个未填方块 。 我们证明NP 完成决定目标方块是否可以填满, 由直线平面单体单体3SAT的缩写 。