Original puzzle laboratory

Six ways to think like a casebook

Short, original challenges based on reasoning modes—not copied programme puzzles, props or dialogue.

Reviewed guide · Sources & corrections
A puzzle worktable with original blank grid, route sketches and reasoning tools
Original fan artworkUnofficial archive commissionAI-assisted original fan artwork · not programme material
Puzzle laboratory

Reasoning should feel playable

The worktable turns constraints, routes, language and geometry into an inviting place to experiment.

Sequence

Four visits occur at 09:05, 09:20, 09:35 and 09:50. Ada arrives before Ben; Cleo is last; Ben is not second. Who is second?

Hint 1 · Place the fixed visit

Cleo is last, so begin by fixing the fourth position.

Hint 2 · Eliminate the impossible slot

Ben cannot be second, and Ada must appear before Ben.

Hint 3 · Show the reasoning

Ada must be first, Cleo fourth and Ben third, leaving Dara second.

Testimony

Exactly one statement is true. Ada: “Ben did it.” Ben: “Cleo did it.” Cleo: “Ben is lying.” Who is consistent with the rule?

Hint 1 · Test, do not guess

Try each possible culprit and count how many statements become true.

Hint 2 · Protect the rule

The correct candidate must leave exactly one truthful statement.

Hint 3 · Show the reasoning

If Cleo is responsible, Ben’s statement alone is true.

Route

A route must visit Gate before Bridge, and Library immediately after Bridge. Which route works?

Hint 1 · Keep the pair together

Bridge and Library form a two-stop block because Library must immediately follow Bridge.

Hint 2 · Position the gate

The remaining rule places Gate before that two-stop block.

Hint 3 · Show the reasoning

Gate–Bridge–Library satisfies both the ordering and adjacency constraints.

Geometry

A ball travels east, rebounds from a vertical cushion and continues at the equal reflected angle. Which general direction follows?

Hint 1 · Name the surface

A vertical cushion changes the horizontal part of the ball’s motion.

Hint 2 · Preserve the angle

The rebound mirrors the incoming path rather than creating a new angle.

Hint 3 · Show the reasoning

Reflection reverses the horizontal component while preserving the angle.

Language

Which word means both a written account and something to achieve?

Hint 1 · Change grammatical role

Look for one spelling that can work as both a noun and a verb.

Hint 2 · Connect document and achievement

One meaning is an account; the other is something a competitor may set.

Hint 3 · Show the reasoning

“Record” can be a documented account and, as a verb, an achievement to register; the ambiguity is the point of the exercise.

Identity

Two identical folders are swapped. Only one has a torn lower corner. What evidence survives the swap?

Hint 1 · Ignore movable information

Position and label colour can change when the folders are swapped.

Hint 2 · Find the persistent property

Look for evidence physically attached to one folder.

Hint 3 · Show the reasoning

A persistent physical property survives a change of position or label.

All six challenges are original instructional exercises. They demonstrate reasoning habits and do not reveal episode solutions.

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