Undead

Undead is an elegant grid logic puzzle: fill the grid with ghosts, vampires, and zombies so that the number of visible monsters from each edge matches the clues—accounting for how each creature appears (or doesn’t) in mirrors.

Set on a rectangular grid, the goal is to populate the empty cells with ghosts, vampires, and zombies—three distinct types of supernatural beings—based on numerical clues provided along the edges.

Each clue indicates how many monsters are visible when looking into the grid from that direction, but here’s the twist:

• Ghosts are invisible in mirrors (i.e., they cannot be seen when viewed diagonally).
• Vampires are only visible in mirrors (i.e., they appear only when viewed diagonally).
• Zombies are always visible, whether viewed orthogonally (straight) or diagonally (in mirrors).

The grid contains mirrors along its diagonals (represented implicitly by the viewing directions), so your line of sight from a clue includes both straight and diagonal paths—depending on the monster type. Using these visibility rules and the edge clues, you must deduce exactly which creature occupies each cell.

Every puzzle has a unique solution that can be reached through pure logical deduction—no guessing required. The challenge lies in juggling the three visibility behaviors while satisfying all row and column constraints simultaneously.

Fill every grid square that does not contain a mirror with either a Ghost, a Vampire, or a Zombie.

The numbers around the edges of the grid indicate how many monsters are visible when you look directly into the grid from that position—along a row or column. Visibility depends on the monster type:

• Zombies are always visible.
• Ghosts are visible only when reflected in at least one mirror (i.e., seen diagonally).
• Vampires are visible only when not reflected in any mirror (i.e., seen orthogonally).

(Taller towers block the view of shorter ones behind them. For example, the sequence 2, 1, 4, 3, 5 would produce a clue of 3 from the left—because the 1 is hidden behind the 2, and the 3 is hidden behind the 4. From the right, the same sequence would yield a clue of 1, since the 5 hides all the others.)

Controls:

• To place a monster: click a square to select it, then press the corresponding letter on your keyboard—G or 1 for ghost, V or 2 for vampire, or Z or 3 for zombie.
• To erase a monster: select the square and press Backspace.
• To add or remove a pencil mark (a possible candidate): right-click the square, then type a letter. Pencil marks help you keep track of monsters that might belong in that cell.
• To mark a clue as satisfied: left-click the clue to grey it out. Click it again to unmark it.

Tip: On mobile devices, you can perform a "right-click" by using a long press.