/usr/share/games/BlocksOfTheUndead/assets/lvls/1/6.txt is in blocks-of-the-undead-data 1.0-6.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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//5///
//3///
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///4//
/5/5//
/3/3//
/4/4//
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