Down the C4 Boulevard

A puzzles blog.

[down-the-c4-blvd]

3

An ancient civilization created a writing system that can be read in two directions, as glyphs are paired in mirrored doubles (like "b" vs "d").

To unlock the door, one must arrange fairly heavy stone blocks with letters on them in a 5x5 grid, with one stone missing on purpose for the movement to be possible. The last letter is known.

Fun twist could be to make the text on the grid similar to SATOR AREPO TENET OPERA ROTAS - Readable in any direction when put in a 5x5 grid.

[down-the-c4-blvd]

2

A set of 8 coins. On one side, they are black, on the other - white.

Goal is to write down a binary UTF-8 message by throwing coins. There are two problems: 1) Each coin has a 50/50 chance of falling either black or white, one or zero. 2) Every throw's result stacks up to automatically turn a decided coin out of the set upside down. This takes three throws: First to decide if the turned coin is going to be in one half of the set, or the other. Then, out of the new half-set, a quarter-set is decided the same way, and out of that, the final coin flip decides which of the two in the quarter-set coins is going to be turned.

This is an almost impossible puzzle, based mostly on luck alone.

[down-the-c4-blvd]

1

A cube with 3x3 sudokus on each side. Pushing the square with a number on one side makes it switch places with the number on the opposite side of the cube.

To solve it, one must make sure no numeral is repeated on any of the cube's sides.