Just got the 2nd hard badge after setting this game aside for years. It wasn't as hard as I feared it would be. I'd recommend going through the normal levels again, at least the last fifty, to re-familiarize yourself with the patterns. It's all memorization. Extreme limited view mode can also be helpful practice, but I wouldn't spend too long on it. Take note of symbols you get confused with each other and try and find some difference you can use to recognize them more easily. Car, star, and apple were ones like that for me. It also could be helpful to find the shortest accepted answer to type (chess instead of checkerboard, bulb instead of lightbulb, glass), the few moments saved from typing long words can really save you. That's about it for my advice, thanks for coming to my TED talk.
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