This game is the computer version of the coded crossword puzzle.

The playfield is split into three different parts. The main part is the
crossword puzzle, where only a few blocks are revealed with the correct
letter. The rest uses numbers to code the letters or are black (free) blocks.

Beneath the main part is the alphabet part, where each letter will be grayed
once it is used. Right of the main part is the number section, there you can
select a number (and all corresponding blocks in the crossword puzzle will be
highlighted) and assign it a letter by typing it.

Your job is now simple (at least in theory), you have to assign the correct
letters to each number. As soon as that happens, you have completed the board,
and depending how fast you were, you may get into the highscore (which is time
based).

Unlike with a real coded crossword puzzle, you have the opportunity to get
help from the computer, i.e. to check if the current letter<->number
assignment is correct or even to completely reveal the board. However, each of
these help results in a time penalty, the amount of penalty depends on how big
the help was.

Coded X-Word