Very simple... but for its purpose and the timeframe it was made in, I think it's still admirable, I know I couldn't do better in 2.5 days :D Could use more items, some additional mechanic other than the battery (maybe battery and damage be separate things?), as well as something you can do other than just move in four directions (e.g. spend battery power to rush).
This game could benefit a lot from better writing - I get the feel it was auto-translated (e.g. with Google Translate), but you really need to have someone fluent in English write your text. The puzzles also get a bit repetitive after a while, just a matter of looking up a combination in one place and entering it in another. But with more polished sounds, animation and writing, it would still be a fun pastime.
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