Pocket Puzzles for Big Brains - Halloween Haunts

Ready to do some spine-tingling solving? Challenge a variety of spooky creatures to a battle of wits! This book contains 130 deductive reasoning puzzles themed around Halloween, including instructions, suggested techniques, and solutions. Why not exercise your brain and work off some of the candy from Trick-or-Treating?

Pocket Puzzles for Big Brains: A lot of fun in a little book!

What’s Inside

13 types of grid puzzles, 10 of each
Difficulty ranges from easy to hard as you progress through the book
Instructions and examples for each puzzle
Basic solving tips to help you get started
Solutions at the back
Book interior is black and white

Puzzles Featured

Candy Box

Everyone loves candy, so you picked up a gift box. The problem is, they only want a specific set of pieces, and none of them can touch each other, even diagonally. Can you deduce which of the possible placements to fill in with the candy that fits their preference?

The requested candy pieces are shown outside the grid. All of them must be used exactly once.
Candy pieces may be rotated.
No candy piece in the grid may touch any other piece in any direction.
Some grids have black cells with no candy.
Harder puzzles may include two-way candy pieces that, if used, can only be part of one candy.

Cobwebs

A cluster of spiders looked at each other from their separate webs, and agreed that they could catch far more food if they worked together. So they decided to connect their webs. This unique species has numbers on their backs, which limits how many web strands they can weave. Can you help them catch dinner?

Connect all spider’s webs into a single group, using no more than two strands between each pair of webs.
Each strand must be a straight horizontal or vertical line connecting 2 webs.
Strands may not cross each other or skip a web in the way.
Numbers on the spider’s back indicates how many total strands are connected to their web.
All webs must form one group, so any spider could walk to any other web via the strands.

Creature

Igor! The flesh is loose on my masterpiece! Sew it together, following my specifications exactly – quickly, for a storm is approaching, and we must bring him to life tonight!

The creature’s face is divided up into regions.
Each region must be attached to every adjacent region with exactly one stitch.
A stitch consists of exactly two bolts in orthogonally adjacent cells, connected by your sewing.
Numbers outside the grid indicate how many bolts are in that row or column.
Unnumbered rows or columns have an unknown quantity of bolts.

Doppelgangers

The masquerade ball is in full swing, but you realize that shapeshifting monsters have mixed into the crowd. Fortunately, they don’t fully grasp logical instructions. Many of your guests wore the same costume, and you ask them to stand in a grid where nobody in any row or column is dressed the same. Any duplicates must be doppelgängers!

Shade cells so that all remaining unshaded cells have no duplicates in any row or column.
There are 10 different costumes, but they might not all appear in a given row or column.
Shaded cells may not be orthogonally adjacent to another shaded cell.
Unshaded cells must form one contiguous orthogonally connected area.

Flee the Castle

You’ve awakened trapped in the vampire castle, and all the doors are hidden! Can you figure out which rooms contain certain death, as well as the way to escape the castle, avoiding vampires, but touching each cross for protection?

Each room must be completely shaded, or completely unshaded.
Cells with symbols (you, vampires, crosses, and the door) are all unshaded.
No 2×2 area may be the same color (shaded or unshaded)
All unshaded cells must form an orthogonally continuous area, without creating a loop.
The final escape path must be a single-cell-wide path which passes through all crosses, and avoids all vampires.

Ghost Hunt

You’ve been hired to examine a warehouse that’s rumored to be haunted. Your meter shows the total number of ghosts it detected. After a few short-range tests around the warehouse, you think you can exorcise them all now.

Each number indicates how many ghosts are in the cells immediately around that location, including diagonally.
No ghost shares a cell with a number.
The meter displays the total number of ghosts in the grid.

Haunted Mirrors

While exploring the countryside, you come across a strange square castle that’s rumored to be inhabited by monsters. While you don’t see a way inside, there do appear to be windows all around that you can look into. Can you identify what monsters are where in the castle?

The total of each monster type is given.
Numbers outside the grid count how many times a monster is seen from that spot looking directly into the castle.
Mirrors are double-sided, and reflect line-of-sight 90 degrees.
Vampires cast no reflection, but are visible when seen directly.
Ghosts are invisible, except when seen in a reflection.
Zombies are always visible.
Seeing a cell more than once might count a monster again.
Monsters appear in all of the empty grid cells.

Invisible Sudoku

Can you solve a jigsaw sudoku puzzle with invisible walls? The sudoku part might be easy enough – fill in the grid with numbers and don’t repeat them in any row or column. However, you also can’t repeat them in an irregular region that you can’t see!

Fill in the grid with numbers from 1-X, with X being the size of the grid.
Digits may not repeat in any row, column, or irregular region.
Invisible walls form the boundaries of each region.
Skulls mark intersections of three walls.
Intersections without a skull may not have a branching wall.

Math Web

Super-intelligent spiders have been studying basic arithmetic and integrating it into their webs. Given a few clues, can you unscramble the operations they used and deduce the sequence from the center to the outside of the web?

Each ring only contains single digit totals, calculated one at a time in a straight line (radial) from the center to outside the web. These numbers may not be lower than 0 or higher than 9.
Eggs on each frame contain the calculations used from one ring to the next. Their positions are scrambled, but all will be used. Zeros will never be a multiplication or division operation.
A number on a spider’s back indicates the difference between digits in the cells to its left and right.

Mirror Akari

It’s the spooky season, and what’s more spooky than a darkened hallway? Place jack o’lanterns to light up every cell in the grid. Use the mirrors to your advantage.

Walls with numbers indicate how many jack o’lanterns must be orthogonally adjacent. Diagonally adjacent placements do not count against this limit.
Walls without numbers may have any number of adjacent jack o’lanterns.
Jack o’lanterns shine as far as they can in all 4 orthogonal directions. They may not be hit by light from another lantern.
Mirrors are double-sided (unless against a wall) and reflect light 90 degrees.

Monster Mash

After a late night working in the lab, you looked out from the balcony and found an eerie sight! Three types of local monsters have begun arranging themselves into groups. The rules seem pretty simple, but where will the rest go?

The grid is divided into 3-cell regions. Each cell must contain one monster.
Each region must contain either three monsters of the same type, or one each of all three different monsters.
Orthogonally adjacent cells of different regions may not contain the same monster.

Trick or Treat

Every sugar-addicted kid looks forward to one thing in October – collecting a mountain of candy while Trick-or-Treating! Plan the perfect route through this neighborhood so that you hit every house, while making a complete loop that covers all the ground.

Draw a single closed loop that doesn’t branch or cross itself.
You must pass through every cell in the grid one time each.
At each house, you must make a 90-degree turn in that cell.
You must also make one and only one turn between each pair of houses.

Zombie Fort

The zombies are invading the forest! Fortunately, you’re VERY fast at building walls. Can you keep all the villagers safe from the zombie horde?

Draw a single closed loop between the trees in the forest, to represent the protective wall.
All villagers must be inside the wall, and all zombies must remain outside it.
Numbers indicate how many wall segments surround that cell.
Wall segments must be orthogonal lines between two trees.
The wall may not branch or cross itself.