1)   Pick-a-Word 1
Select longest valid words, to be replaced by the incoming letters.
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 2)   Cross-Numbers 1
Arrange the numbered tiles in natural order, by moving the rows and columns.
cross-numbers, xnumbers, puzzles, sam lloyd, tiles, 15, Play, logical, funny, games,

 3)   Cross-Colors 1
Change the colors on a row or column, move them, and make the same color.
cross-colors, xcolors, puzzles, sam lloyd, tiles, 15, Play, logical, funny, games,

 4)   Pick-a-Line 1
Select longest lines of identical balls, to be replaced by the incoming balls.
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