MIT Mystery Hunt Puzzle Index: Category Index

MIT Mystery Hunt 2022 Dancing Triangles

arukone

See Number Link puzzle

Bag puzzle

See Corral puzzle

Balance Loop logic puzzle

In this closed-loop-drawing puzzle, the loop passes through all the cells with circles. At white circles, the line travels the same number of cells on either side of the circle before turning, and at black circles, it travels a different number of cells on each side before turning. A number on the circle tells the sum of the straight segments on each side of the circle up to the next turn, even if the path goes through other circles before turning.

Battleships (puzzle)

The standard form of this puzzle consists of a grid with numeric clues outside the grid and possibly parts of the solution given inside the grid. You have to locate a fleet of ships (usually 1 of length 4, 2 of length 3, 3 of length 2, and 4 of length 1) in the grid, such that no two ships occupy adjacent cells (even diagonally) and the number of occupied cells in each row and column matches the given number. Givens may appear as a circle (length 1 ship), square (interior piece of a length 3 of longer ship), half-square-half-circle (end of a length 2 or longer ship), or wavy lines (no ship).

black and white (logic puzzle)

In the standard form of this puzzle type, a grid is given with black circles in some squares and white circles in others, but mostly blank. To solve it you must fill in either a white circle or a black circle in each box so that all the white circles form a single orthogonally connected group, and the black circles also form such a group, and no 2x2 region is all the same color.

MIT Mystery Hunt 2015 Polyglot
MIT Mystery Hunt 2023 Make Love or War

Black Box (game)

Black Box is a puzzle-like game where one player tries to determine the locations of hidden atoms in a grid by observing how the atoms reflect rays entering the box from various locations. It can also be solved as a puzzle, given a predetermined set of ray results.

MIT Mystery Hunt 2013 Aria

Bridges puzzle

See hashiwokakero

calcudoku

See KenKen

Cave puzzle

See Corral puzzle

Cell Structure puzzle

See Nurikabe

Corral puzzle

The standard form of this puzzle is a grid with numbers in some cells. A single closed loop is to be drawn along the edges of the grid so that all the numbers are inside the loop, and the number of squares in the row and column through each number, going up to the first part of the loop encountered in each direction, and counting the cell with the number once, equals the number. The instructions for Cave have you shade in the cells outside the loop, but with rules which make it functionally the same puzzle.

MIT Mystery Hunt 2008 Chimera
MIT Mystery Hunt 2013 Portals
MIT Mystery Hunt 2014 Magic Mushrooms
MIT Mystery Hunt 2020 Cactus Ranch
MIT Mystery Hunt 2022 Dancing Triangles
MIT Mystery Hunt 2023 Flooded Caves

Country Road (puzzle type)

This Nikoli puzzle type has a grid broken into multiple rooms. Some rooms contain a number. You must draw a loop through the grid, entering and exiting each room once, and using the number of squares indicated in rooms with a number. Orthogonally adjacent cells in different rooms cannot both be unused.

MIT Mystery Hunt 2018 Laratel WF-15 Fusion Reactor

Creek puzzle

Creek is a Nikoli logic puzzle type. A grid contains circled numbers at some of its intersections. Blacken some squares so that of the 4 squares around each number, that number of squares are black, and so that the empty squares form a single orthogonally connected group.

MIT Mystery Hunt 2013 Portals

Cross Products (Cross Sums variant)

This is like a Cross Sums except the product of the digits in each entry is given, rather than the sum.

MIT Mystery Hunt 2008 Cursed
MIT Mystery Hunt 2024 Why The Romans Never Invented Logic Puzzles

Cross Sums

This is one of the most popular numerical puzzle types. In its standard form, a crossword-like grid has clues in the grid providing the sum of the digits to be entered in each entry. No zeroes are used and no entry contains any digit more than once.

MIT Mystery Hunt 2001 23
MIT Mystery Hunt 2003 Some Stars
MIT Mystery Hunt 2005 Express Yourself
MIT Mystery Hunt 2007 The Joy of Accountancy
MIT Mystery Hunt 2009 Cross Something-Or-Others (numerous variations)
MIT Mystery Hunt 2011 Technological Crisis at Shikakuro Farms (variant)
MIT Mystery Hunt 2012 The Signs They Are A-Changin’ (variant)
MIT Mystery Hunt 2014 Kroskuro
MIT Mystery Hunt 2017 Stackuro

curved line nonogram

This is what it sounds like. It works much like a standard nonogram except the lines aren't straight. There are numbers on one side of each end of each line which tell the lengths of the consecutive groups of boxes on that side of the line which are shaded - but the boxes may have more or fewer than 4 sides!

MIT Mystery Hunt 2022 Where the Wild Things Are

deficit sudoku

See udoku

Dotty dilemma puzzle

See fences puzzle

Dungeons and Diagrams (logic puzzle)

MIT Mystery Hunt 2023 Reactivation

Easy as ABC puzzle

See End View puzzle

Edel puzzle

MIT Mystery Hunt 2005 Easy as ABC
MIT Mystery Hunt 2010 Sequencer
MIT Mystery Hunt 2016 Paint it Black
MIT Mystery Hunt 2023 Hall of Archaeology

End View puzzle

Also called Easy as ABC, this is a kind of Latin square puzzle in which each row is to be filled with the same set of different letters and some number of blank spaces. Outside the grid, clues indicate the first non-blank at that end of that row or column.

Every Second Turn

See Alternate Corners puzzle

fences puzzle

In the standard form of this puzzle, a grid is presented as dots at the vertices, and some cells contain a number. You must draw a single closed loop along the lattice lines so that for each cell with a number, that number of its 4 sides are used in the loop.

Fill-a-Pix

This is a logic puzzle very much like the Minesweeper game but all the clues you are going to get are provided initially, and spaces with clues may also contain mines (in which case they include themselves in their count). Puzzles without this self-counting behavior are classified under Minesweeper instead.

MIT Mystery Hunt 2010 Queasy Reaction
MIT Mystery Hunt 2022 Where the Wild Things Are

Fillomino puzzle

The standard form of this puzzle consists of a grid where some cells initially have a number. To solve it, fill numbers into the remaining cells so that each orthogonally connected group of the same number consists of as many cells as that number. There may be zero, one, or more than one number given for each group. Also called Filliamond on triangular grids.

MIT Mystery Hunt 2007 Puzzle Editing
MIT Mystery Hunt 2011 Nik-holey
MIT Mystery Hunt 2014 Magic Mushrooms
MIT Mystery Hunt 2019 Connect Four
MIT Mystery Hunt 2022 Dancing Triangles
MIT Mystery Hunt 2023 Hall of Archaeology
MIT Mystery Hunt 2023 World's Largest Logic Puzzle

gattai

See samurai sudoku

Gokigen Naname

See Slant puzzle

Grand Tour puzzle

See path puzzles

Griddlers

Hanjie

hashi

See hashiwokakero

hashiwokakero

The standard form of this puzzle consists of a set of circled numbers aligned to a grid (which is not otherwise given). To solve it, add some horizontal or vertical "bridges" between the circled numbers such that the number of bridges terminating at each number is the same as that number. At most two bridges may extend in each direction from a number, and bridges never intersect or jump over numbers.

heteromino (logic puzzle)

In this logic puzzle type, a grid is provided with some black squares. You must divide the white squares into groups of three (triominoes) so that two triominoes of the same shape and orientation do not touch orthogonally.

MIT Mystery Hunt 2007 Puzzle Editing
MIT Mystery Hunt 2011 Nik-holey
MIT Mystery Hunt 2013 Portals
MIT Mystery Hunt 2014 Magic Mushrooms
MIT Mystery Hunt 2022 Dancing Triangles

Heyawake

This puzzle consists of a grid with heavy outlines dividing it into a set of rectangular regions of various sizes. Some of the individual cells are to be shaded, such that no two adjacent cells are ever shaded, all the unshaded cells form a single orthogonally connected group, and in regions with a clue number, the number of shaded cells equals that number.

Hidato puzzle

A grid with some cells filled in with numbers is given. You must fill in the remaining cells so that each number from 1 to N is used once, and you can walk a path from 1 to N with orthogonal and diagonal steps. Numbrix is a variant on Hidato where diagonal steps are not allowed.

MIT Mystery Hunt 2022 Dancing Triangles

Hitori

The standard form of this puzzle consists of a grid initially filled in with a number in every cell. Some of these cells are to be shaded such that no two adjacent cells are shaded, all the unshaded cells form a single orthogonally connected group, and no two unshaded cells in the same row or column contain the same number.

MIT Mystery Hunt 2007 Puzzle Editing
MIT Mystery Hunt 2008 Witness 1 Meta
MIT Mystery Hunt 2011 Nik-holey
MIT Mystery Hunt 2014 Magic Mushrooms

Index Sums puzzle

See kakurasu

Islands in the Stream puzzle

See Nurikabe

kakurasu

Kakurasu is a grid-based logic puzzle. Given a grid and sums for each row and column, black some cells such that the values of the black cells add up to the given sums. A black cell in the first position in its row/column counts as 1 toward the sum; one in the second position counts as 2, and so on.

MIT Mystery Hunt 2021 Extensive

Kakuro

See Cross Sums

KenKen

The standard form of this Latin square puzzle consists of a grid divided into a number of heavily outlined regions, each of which contains a small clue number and a mathematical operation. The grid is to be filled in with the numbers from 1 to N, not repeating a number within a row or column, such that the result of applying the operation in each region to the numbers filled into that region equals the clue number. IN some variants the operations may be omitted and only the numbers given.

MIT Mystery Hunt 2010 Holding Pattern
MIT Mystery Hunt 2013 Agricultural Operations
MIT Mystery Hunt 2016 The Fire Swamp
MIT Mystery Hunt 2022 How To find a Component

killer sudoku

Like regular sudoku but there are cages made of dashed lines around sections of a few cells with a clue giving the sum of the digits in the cage. Digits cannot repeat inside a cage.

MIT Mystery Hunt 2022 The Downtown Murders

kurodoko

See kuromasu

kuromasu

A Nikoli puzzle type featuring a grid with circled numbers in some cells. The clues have the same meaning as in corral, each indicating the total number of squares, including itself, that you can see looking in the orthogonal directions up to the edge of the grid or the first wall. In this case, the walls are isolated black cells which cannot touch orthogonally. The white cells must remain a single orthogonally connected group. The English name for this puzzle, "where is black cells?" has bad grammar, and could describe dozens of puzzles, but is nevertheless the name used.

MIT Mystery Hunt 2023 Reflective Screen
MIT Mystery Hunt 2023 Tissues

Latin squares

A Latin square is simply one where the same set of letters, numbers, or other symbols appear in each row and each column. A number of standard puzzle types (see End View, KenKen, skyscrapers, star battle, and sudoku) are based on forming a Latin square under additional constraints, and those puzzles are listed under those categories.

MIT Mystery Hunt 2000 Isn't It Romantic?
MIT Mystery Hunt 2012 Twosquare
MIT Mystery Hunt 2016 Roller Coaster
MIT Mystery Hunt 2021 The Greatest Jigsaw

Light Up puzzle

See Akari puzzle

Link-a-Pix

Link-a-Pix is a puzzle type invented by Conceptis. A grid contains scattered numbers in various colors. Like numbers are to be connected using orthogonally connected paths which don't overlap, each as long as the number they connect, and colored the same as the numbers they connect, with the result forming a picture.

MIT Mystery Hunt 2013 Transit Links

LITS puzzle

LITS is a Nikoli logic puzzle type. A grid is initially divided into several heavily outlined regions. Within each grid you must blacken 4 squares forming one of the tetromino shapes L, I, T, or S such that no 2x2 grid section is completely blackened (thus, the O tetromino is not allowed), all the tetrominoes form one orthogonally connected group, and no two tetrominoes of the same type touch along an edge.

MIT Mystery Hunt 2013 Portals
MIT Mystery Hunt 2017 Changing Rooms
MIT Mystery Hunt 2022 Dancing Triangles

Loop and Block puzzle

Shade some cells and draw a closed loop through the unshaded ones without clues. Each clue tells how many orthogonally adjacent cells share at edge with the clue cell. This is similar to yajilin except the clues are based on adjacency rather than cells pointed to by an arrow.

MIT Mystery Hunt 2022 Dancing Triangles

Loop the loop puzzle

See fences puzzle

magnet logic puzzles

In the standard form of this puzzle, a grid is broken up into 2-cell regions, some of which are to be filled in with a + in one cell and a - in the other, so that the total number of +s and the total number of -s in each row and column equal the numbers given outside the grid, and two of the same symbol are never in orthogonally adjacent cells.

MIT Mystery Hunt 2008 Monopoles

Masyu

In the standard form of this puzzle, a grid is provided with empty or filled circles in some cells. A single closed loop is to be drawn through some cells so that the loop passes through every circle, turning in each filled cell (but not turning just before or after the filled circle), and going straight through empty circles (but turning before and/or after the empty circle).

MIT Mystery Hunt 2007 Puzzle Editing
MIT Mystery Hunt 2012 Evil Influence
MIT Mystery Hunt 2014 Oyster Card
MIT Mystery Hunt 2015 Polyglot
MIT Mystery Hunt 2016 Sleeping Beauty Meta
MIT Mystery Hunt 2019 Schematics
MIT Mystery Hunt 2020 The Ferris of Them All
MIT Mystery Hunt 2022 How To Make the Right Move
MIT Mystery Hunt 2023 Hall of Archaeology

math maze

Math maze is a path puzzle with Battleships-style clues that tell you how many squares in each row and column are part of the path. This makes it a relative of the snake puzzle but in math mazes only the head and tail are given and the path is allowed to visit squares adjacent to other parts of the path. The grid may have holes which divide rows and columns into parts; in this case clues apply to each part separately. Random Walk contains an example puzzle.

MIT Mystery Hunt 2013 Random Walk

Minesweeper game

Classic video game made popular by its inclusion with Windows 3.1, often presented as a static puzzle with a fixed set of clues. You are to locate a set of mines in the grid, given clues which are not on mines themselves but tell how many of the 8 adjacent squares contain mines. A version where clue squares may contain mines (and count their own mine if they do) is called Fill-a-Pix.

miracle sudoku

Miracle sudoku adds two constraints on top of normal sudoku: Two of the same number cannot be a king's move or knight's move apart, and consecutive numbers cannot be adjacent within a row or column.

MIT Mystery Hunt 2021 ★

mirror logic puzzles

In the standard form of this puzzle, you have to determine where to place two-sided mirrors at either or two diagonal directions in some cells, so that each pair of identical clues outside the grid is connected by a path of orthogonally connected cells through the grid which bends at (and only at) mirrors, in the directions which do not cross the mirrors. A path may use the same cell twice (either passing straight through an empty cell twice in different directions, or bouncing off both sides of the same mirror)

MIT Mystery Hunt 2005 Hall of Mirrors
MIT Mystery Hunt 2005 Reflecting Pool
MIT Mystery Hunt 2008 The Cult of Helios
MIT Mystery Hunt 2009 Space Ghosts, Coast to Coast
MIT Mystery Hunt 2010 Sequencer
MIT Mystery Hunt 2011 The Light World
MIT Mystery Hunt 2012 Sheila Sunshine Meta
MIT Mystery Hunt 2017 Mirrorball
MIT Mystery Hunt 2021 Bounce House
MIT Mystery Hunt 2023 Reflective Screen

Mirror Universe puzzle

Mirror Universe is a variation on Spiral Galaxies in which you must divide the grid into symmetric regions, with the center of each region marked. In addition to the centers of rotational symmetry of the original puzzle, Mirror Universe also has regions with mirror symmetry. For these regions, some portion of the axis of symmetry is given.

MIT Mystery Hunt 2023 Reflective Screen

multidigit sums puzzle

In this puzzle type, you are to place digits in some cells so each row and column has the indicated set of digits. Clues given for rows and columns indicate the sum f the entries in the row or column, counting each group of adjacent digits as a multi-digit number.

MIT Mystery Hunt 2023 Reflective Screen

multiple answers to logic puzzles

MIT Mystery Hunt 2005 Simple Unassuming Logic Puzzles
MIT Mystery Hunt 2007 Puzzle Editing
MIT Mystery Hunt 2016 A Quick Sudoku
MIT Mystery Hunt 2021 Fun With Sudoku

Nonograms

MIT Mystery Hunt 2013 Portals
MIT Mystery Hunt 2023 Hall of Archaeology

Norinori puzzle

Norinori is a Nikoli logic puzzle type. A grid is initially divided by heavy borders into a number of regions. Within each region, blacken two squares so that every black square shares an edge with exactly one other black square (not necessarily in the same region).

not alone (logic puzzle)

In the standard form of this puzzle type, you are given a grid in which some squares contain a white circle or a black circle. You are to fill in white or black circles in the empty squares so that nowhere does a white circle have black circles both on its immediate left and right, or both immediately above and below. A single circle "alone" on the edge of the grid is allowed. In addition, each row and each column has exactly half its circles black and half white.

MIT Mystery Hunt 2016 A Round at the Golf Course
MIT Mystery Hunt 2020 Tunnel of Love
MIT Mystery Hunt 2021 Dolphin
MIT Mystery Hunt 2023 Numberlink

Number Link puzzle

In Number Link, a grid is given with two of each number. You have to connect the matching numbers with paths connecting squares orthogonally, so that no paths overlap. Generally, all the squares must be used.

number place

See sudoku

Numbrix

See Hidato puzzle

Nurikabe

This is the most common "island" puzzle. In the standard form, a grid is provided with numbers in some cells. Some of the unnmubered squares are to be shaded so that the shaded squares form a single orthogonally connected group, and each orthogonally connected group of unshaded cells contains exactly one number, which is the size of that group.

MIT Mystery Hunt 2007 Puzzle Editing
MIT Mystery Hunt 2008 Chimera
MIT Mystery Hunt 2011 Nik-holey
MIT Mystery Hunt 2012 Blackout
MIT Mystery Hunt 2013 Portals
MIT Mystery Hunt 2014 Magic Mushrooms
MIT Mystery Hunt 2014 The Lion and the Unicorn
MIT Mystery Hunt 2019 Invisible Walls
MIT Mystery Hunt 2022 Trickster Tales
MIT Mystery Hunt 2022 🔔🦇🦇🦇
MIT Mystery Hunt 2023 Hall of Archaeology

Nuruomino

See LITS puzzle

paint by numbers (logic puzzle)

In the standard form of this puzzle, a large empty grid is provided, along with a set of clue numbers on each row and each column. Some cells are to be shaded so that each row or column contains groups of shaded cells, separated by one or more blank cells, with the lengths of these groups matching the provided clue numbers, in order. There are common variants where cells may be shaded in different colors or half-shaded with triangles; in these variants, the different colors or triangles in each row are normally given in the clues, and the requirement of a blank cell between groups is waived if they are different types, or any types of triangles. In the standard form of this puzzle, a large empty grid is provided, along with a set of clue numbers on each row and each column. Some cells are to be shaded so that each row or column contains groups of shaded cells, separated by one or more blank cells, with the lengths of these groups matching the provided clue numbers, in order. There are common variants where cells may be shaded in different colors or half-shaded with triangles; in these variants, the different colors or triangles in each row are normally given in the clues, and the requirement of a blank cell between groups is waived if they are different types, or any types of triangles. Another variant allows oversized cells in the grid which cover multiple rows and/or columns, but count as one cell in the clues.

path puzzles

There are many other standard puzzle types which are path puzzles, where the point of the puzzle is to determine a path through a grid from given clues. This puzzle type is used for ones that don't fit into any of the standard types. Grand Tour is a name for a basic path puzzle - parts of the path are given and you must draw a loop visiting each cell once; old USPCs called this Round Trip. Purenrupu (pure loop) is another basic path puzzle; in this one, there are some shaded squares and you must make a loop through eachunshaded cell.

MIT Mystery Hunt 1996 11C
MIT Mystery Hunt 2001 Numerology
MIT Mystery Hunt 2014 Build Your Own Sudoku
MIT Mystery Hunt 2015 Cube
MIT Mystery Hunt 2015 Ocean Meta Meta
MIT Mystery Hunt 2016 Roller Coaster
MIT Mystery Hunt 2018 A Learning Path
MIT Mystery Hunt 2018 Shoal Patrol
MIT Mystery Hunt 2018 Submarine Patrol
MIT Mystery Hunt 2020 Backlot

Pentomino Minesweeper (logic puzzle)

This is a variation on the standard Minesweeper puzzle type where the mines are forced to lie in groups of 5 orthogonally connected mines, usually all different and without the groups touching, even diagonally.

MIT Mystery Hunt 2012 Blackout

Pic-a-Pix

Picross

MIT Mystery Hunt 2002 Sampler

Proof of Quilt

See Shakashaka puzzle

Purenrupu

See path puzzles

Railroad Crossing puzzle

The standard form of this puzzle consists of a grid with the numbers 1 to N in some squares and crosses in some other squares. You must draw a path through all squares in the grid, going through the numbered stations in order and going straight at each station, and only crossing itself at the marked crosses.

Railroad Tracks puzzle

See Railroad Crossing puzzle

River Crossing logic puzzles

This is for variations on the classic puzzle where a farmer is trying to cross a river with a wolf, a goat, and a basket of cabbages. He can't leave the wolf unattended with the goat, since it will eat the goat, nor can he leave the goat unattended with the cabbages, but his boat can only carry one of the three things besides himself. Even classically there are many variations on this.

MIT Mystery Hunt 2009 Our Crew is Replaceable. Your Package Isn't.

rotator logic puzzle

MIT Mystery Hunt 2016 Replication

Round Trip puzzle

See path puzzles

samurai sudoku

Two or more Sudoku grids overlap, typically by one of the 3x3 regions. The numbers in the overlap must satisfy each Sudoku .

Seeking Syren (logic puzzle)

MIT Mystery Hunt 2010 Seeking ~~Syren~~ Scotchy

Shakashaka puzzle

A grid of white and black cells is given, with numbers in some black cells. You are to place triangles (half-squares which divide the square diagonally) in some white cells so that the remaining white areas form squarea and rectangles (orthogonal or tilted).

MIT Mystery Hunt 2022 Boom Shakashaka!

Sheep and Wolves

Sheep and Wolves is a variant on Fences (Slither Link) invented by Dave Tuller. In addition to the usual numerical clues, you can get clues which are sheep (which must lie inside the fence) or wolves (which must lie outside).

MIT Mystery Hunt 2016 To Serve and Protect

shikaku

In the standard form of this puzzle, you must divide the given grid along the grid lines into rectangles so that each rectangle contains exactly one of the given numbers, which is the area of its rectangle.

MIT Mystery Hunt 2011 Technological Crisis at Shikakuro Farms (variant)
MIT Mystery Hunt 2014 Marking Territory
MIT Mystery Hunt 2016 Quilt by Association
MIT Mystery Hunt 2022 The Hound of the Vast-Cur-Villes

signal loop (logic puzzle)

In this logic puzzle type, a grid is provided with black or white circles in some cells. You must draw a loop through all the cells except the ones with black circles. The loop cannot turn on squares with white circles. In the variant Antisignal Loop, the loop avoids squares with white circles and turns in squares with black circles.

MIT Mystery Hunt 2005 Simple Unassuming Logic Puzzles
MIT Mystery Hunt 2007 Clash of the Titans
MIT Mystery Hunt 2009 Growth Involves Reconstructing Legos
MIT Mystery Hunt 2014 Magic Mushrooms
MIT Mystery Hunt 2023 Hall of Archaeology
MIT Mystery Hunt 2023 Reflective Screen

skyscrapers puzzle

In the standard form of this Latin square puzzle, you must fill in the numbers 1 to N in the cells of the NxN grid so that no number is repeated in a row or column. Additionally, if the numbers are taken as the heights of buildings, the numbers outside the grid tell how many buildings can be seen in that row or column from that side of the grid, where taller buildings hide shorter buildings that are behind them.

Slalom puzzle

See Slant puzzle

Slant puzzle

A Nikoli puzzle type. A grid is given with numbers at some intersections. The goal is to draw a diagonal line through each cell so that at each numbered intersection, that number of the diagonals meet there. The diagonals are also forbidden to form loops.

MIT Mystery Hunt 2022 Tryst of Fate

Slither Link

See fences puzzle

snake puzzle

The standard form of the snake puzzle contains a single snake whose segments are numbered 1 to N, of which certain segments are filled in initially, including the head and tail. The snake cannot touch itself, even diagonally (only squares with consecutive numbers may be orthogonally adjacent, and only ones with numbers that differ by 2 may be diagonally adjacent). Clues indicating the number of snake segments in certain rows and columns are are given. Black squares indicating spaces the snake cannot pass through may be given.

MIT Mystery Hunt 2002 Sampler (variant)
MIT Mystery Hunt 2012 Let's Put on a Hit (spotted snake variant)
MIT Mystery Hunt 2013 Portals
MIT Mystery Hunt 2013 Snake (variation)
MIT Mystery Hunt 2022 Dancing Triangles

Spiral Galaxies puzzle

A grid has some circles, which may be in the centers of cells, on the grid lines, or on the grid intersections. Divide the grid into regions so that each circle is in a separate region, all regions are rotationally symmetric, and each region has a circle at its center. Sometimes the circles are colored and you shade the regions in the resulting grid based on the circle colors.

MIT Mystery Hunt 2019 Lantern Festival
MIT Mystery Hunt 2023 Reflective Screen
MIT Mystery Hunt 2023 Book of Fixed Stars

ssudoku

This variant of sudoku features regions which are larger than the size of the grid. They contain each digit once but also contain repeated digits. This compromises the "naked singles" solving strategy from regular sudoku.

MIT Mystery Hunt 2012 Equal Billing

Star Battle (logic puzzle)

The standard form of this puzzle works as follows: A square lattice is divided into irregular polyomino regions. Enter some stars so that each row, each column, and each region contains exactly two stars, and no two stars are adjacent, even diagonally.

MIT Mystery Hunt 2012 Equal Billing (variant combined with sudoku)
MIT Mystery Hunt 2016 Reaching for the Stars
MIT Mystery Hunt 2017 Changing Rooms
MIT Mystery Hunt 2019 Battle of the Network Stars
MIT Mystery Hunt 2022 Heavenly Bodice

Statue Park puzzle

Statue Park puzzles are an original invention of Palmer Mebane. A set of polyominoes are to be placed into a grid. They can touch at a corner but not along an edge. The unused space must form a single edge-connected unit. Black circles must be covered by polyominoes; white circles must not.

MIT Mystery Hunt 2013 Portals
MIT Mystery Hunt 2015 Polyglot
MIT Mystery Hunt 2022 Dancing Triangles

sudoku

In the standard form of this puzzle type, a 9x9 grid is divided into 3x3 sections with heavy bars. The grid is to be filled with the digits 1 to 9 (some initially provided) so that no number is repeated in a row, column, or outlined region. There are many popular variants on this puzzle type, including ones where the diagonals have to contain 1 to 9, ones where the regions are not square, ones where there are restrictions on which numbers can be adjacent, puzzles of different sizes, and many others. See specific variations:

sun and moon (logic puzzle)

In this logic puzzle type, a grid is provided with white or black circles in some squares. You must draw a loop through all the cells so that when the loop goes through two cells of the same color in a row, it doesn't turn between them, and when it goes through two different colored circles, it turns exactly once between them, The loop may turn on a circle.

Sym-a-Pix

MIT Mystery Hunt 2012 Blackout
MIT Mystery Hunt 2013 Portals

Takegaki

See fences puzzle

Tapa

In the standard form of this puzzle, a grid is provided with one or more numbers in some cells. To solve it, shade some empty cells in an orthogonally connected group so that among the 8 cells orthogonally or diagonally adjacent to each numbered cell, the connected group(s) of shaded cells have the size(s) of the number(s) in that cells. (Like paint by numbers except the clues apply to these 8-cell rings instead of rows and columns.)

Tentai Show