TEXT: How to Create Puzzles for RPGs
  Fifth Edition has a lot of cool elements to it that GMs can use:
  combat, exploration, and, of course, plenty of role play. These are
  often considered the four pillars of a tabletop RPG. However, I
  believe that there is a fourth that's just as important: problem
  solving and critical thinking. And it is arguably the most difﬁcult of
  the four to plan properly.
  This article goes in-depth on how to create puzzles for Fifth
  Edition, ﬁrst, introducing common themes, then delivering a step-
  by-step method for adding puzzles to your own adventure.
  Part 1. Common Themes in
  Tabletop RPG Puzzles
  Having read through a number of tabletop RPG modules and
  adventures, I've noticed that there are a lot of common themes
  among the various puzzles that appear. This is a list of the types I've
  encountered the most. Of course, this is by no means a deﬁnitive
  list.
  Card Arranging
  The characters (and even the players) are given cards which they
  must arrange to solve the puzzle. Sometimes, the cards act as literal
  puzzle pieces that offer a clue when put together the right way.
  Other times they are clues themselves.
  Example: the characters and players are given three cards that
  seem to read gibberish. However, if they are placed in a "staircase"
  formation, they read "GO DOWN STAIRS."
  Careful Placement
  Certain puzzle solutions require that the characters carefully place
  an object. Sometimes, the object has multiple ways it can be placed,
  offering different beneﬁts (or penalties) where it is placed.
  Example: the characters discover an oddly-shaped sword. There
  are three holes in the ﬂoor. Placing the sword in the correct hole
  opens the door. Misplacing it triggers a trap.
  Classic Games
  Perhaps a little meta, but a puzzle might incorporate elements from
  a classic game such as chess or minesweeper. If the players are
  familiar with the function of the game, they can solve the puzzle in
  no time.
  Example: the characters enter a room where its ﬂoors are marked
  with hexagonal tiles, each with a number on it. The numbers help
  the characters identify the location of traps, similar to how the game
  the numbered tiles in the classic computer game minesweeper does.
  Dual Use Items
  Objects given to the characters may have more than one use.
  Example: a medallion the characters ﬁnd in the ﬁrst act is not only
  the key to an important door, but it serves as compass on a map they
  discovered in the second map.
  Hint at Danger
  Sometimes, a magic item or clue hints that there may be an unseen
  danger somewhere in the challenge.
  Example: while traveling through an ancient temple, the characters
  ﬁnd a sword of reptile slaying just before they have to enter a sealed
  room.
  Illusions
  An element of games that deﬁnitely doesn't see enough use,
  illusions have many functions. They can place powerful illusory
  creatures in the paths of the characters, create hazards where there
  are none, or hide important information.
  Example: the characters open a door, revealing a room with a
  massive pit. The only exit is 40 feet from where they stand.
  However, the pit is an illusion.
  Individual Challenge
  There are challenges that require a single character to solve without
  the help of his/her companions. This could be because the situation
  requires the party to split up (gasp), or something is preventing the
  party from openly communicating, such as magical darkness or the
  silence spell. It might also require a speciﬁc talent or skill the
  character possesses, such as a thief's locking-picking skills or a
  mage's talent for the arcane.
  Example: a secret door opens so long as one of the characters
  stands on a pressure plate. The door automatically closes if the
  character steps off the plate.
  Magic Items
  The characters are given a magic item. While the magic item may
  initially appear to be useless or have a secondary value, it is used as
  part of the puzzle's solution.
  Example: the characters discover a magical gem that reveals the
  path through a maze of invisible force walls.
  Monsters as Helpers
  A few scenarios require the characters to use the monsters present to
  assist them.
  Example: a huge chasm is the only thing between the party and the
  treasure they seek. Floating over the chasm are gas spores. To cross
  to the other side, the characters must use the gas spores as "stepping
  stones" leaping from one spore to the next.
  Meta Challenges
  Meta elements sometimes incorporate details from previous
  scenarios, or sprinkle clues throughout the adventure which don't
  become obvious until the characters reach a ﬁnal puzzle. This works
  especially well as a "red herring" (see below) as these subtle clues
  can distract from immediate puzzles.
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  Example: in each previous puzzle room, the characters discovered
  numbers on the walls painted in red. Initially, they thought that the
  puzzles didn't mean anything. But once they reached the ﬁnal
  puzzle, it's clear that the numbers were supposed to use in a
  combination lock.
  Order of Operations
  Many puzzles have a speciﬁc order in which the characters should
  perform related tasks. Failure to follow the correct order could spell
  danger.
  Example: to get into the next room, one character must press a
  button to open a door, another needs to press a button to disable the
  traps in the room, and a third must press a button to lower a draw
  bridge. Once everyone is in place, the fourth character runs across
  and hits the button that opens the door allowing his/her
  compnanions to join him/her on the other side.
  Props
  Physical props given to the players are a fun way to help visualize
  puzzles.
  Example: if a puzzle involves the characters using a mirror to solve
  it, why not include a mirror?
  Red Herrings
  A red herring is a false clue within the adventure designed to throw
  the characters off the actual clues.
  Example: the characters discover a key in the ancient tomb.
  However, the key doesn't work in any of the tomb's doors.
  Riddles
  A riddle is a question or statement intentionally phrased so as to
  require ingenuity in ascertaining its answer or meaning.
  Example: the sphinx poses the riddle: "What is the creature that
  walks on four legs in the morning, two legs at noon and three in the
  evening?" to which the answer is "man."
  Simple Math
  Often, a puzzle requires the players and their characters to do basic
  arithmetic, numerology, or geometry.
  Example: the characters discover ﬁve doors, each with a sequence
  of numbers. Adding the numbers together in each sequence reveals
  that four of the doors add up to an even number while the ﬁfth adds
  up to an odd number.
  Teamwork
  Teamwork puzzles require the characters to work together to solve
  the problem.
  Example: in order to see all of the clues within a temple, one
  character must ride on the shoulders of another.
  Word Puzzles
  The characters discover word clues which they must decipher to
  pass a challenge.
  Example: the characters discover a word jumble. Putting the letters
  into the correct position, the word spells "BLACK IS THE KEY"
  which tells the characters to use the black key for the door intstead
  of green or red.
  Part 2. How to Create Your
  Own Challenges
  Now that I’ve broken down various styles of puzzles and
  challenges, you should have a decent idea of how to assemble good,
  level-independent challenges for your characters.
  Here are a few steps I’ve ironed out to help in the challenge
  assembly:
  1 – Come up with the solution to the challenge
  The easiest way to create these challenges is to start from the end
  and work your way backward offering the best possible solution.
  You could even start with a map of a room and its obstacles.
  Make sure you include a way out of the room or challenge-area.
  For example, a cylindrical shaped room could have a hole in the
  ceiling that the characters need to escape through.
  Once you have everything in place, work your way backward
  from the solution.
  Try not to overdo certain themes. For example, every challenge
  involving a word puzzle may get boring after a while. Unless, of
  course, your players enjoy word puzzles.
  2 – Create the appropriate handouts
  A majority of the puzzle scenarios in Fifth Edition modules come
  with handouts to help the characters come up with a solution. In
  addition, many of the rooms can be difﬁcult to visualize. It helps to
  create these handouts accurately for the characters to hold, view,
  and use.
  3 – Supply the proper props and clues
  Each scenario begins with a description offering the characters the
  requirements to fulﬁll the challenge. Make sure that your
  descriptions and items give the characters a basic idea of what to do.
  Be sure to sprinkle a few of your challenges with red herrings,
  but don’t overuse it. Otherwise, the players will always be
  suspicious that there’s a red herring present.
  If you choose to offer hints, make sure that the hint cuts straight
  to the core of the solution. For example, if the characters are
  supposed to ignore the cards in a particular challenge, make sure the
  hint tells them to do that. But don’t give away too much!
  4 – When in doubt, “steal” from other sources
  Supposedly, Pablo Picasso once said that “good artists borrow, great
  artists steal.” Don’t be afraid to do the same with your challenges.
  You could get ideas from your Sunday word jumble, or even use
  some of the challenges presented in ofﬁcial Fifth Edition books
  themselves (retooled, of course, if you’re going to sell the ﬁnal
  product).
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