Here is a hack for Super Mario Bros which changes the levels and graphics in the game. A higher degree of difficulty is also a part of the hack.
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TETRIS
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- ???[?? -
?G???o?ꂵ?Ȃ???????n??????i?B
- ?X?e?[?W?\?? -
1-1 2-1 3-1 4-1
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(c)Garuna
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Database match: Super Mario Bros. (World)
Database: No-Intro: Nintendo Entertainment System (v. 20210216-231042)
File SHA-1: EA343F4E445A9050D4B4FBAC2C77D0693B1D0922
File CRC32: 3337EC46
ROM SHA-1: FACEE9C577A5262DBE33AC4930BB0B58C8C037F7
ROM CRC32: D445F698