A quick guide to unlock the secret characters in the game through both methods, there’s relatively few in this game, but they’re quite unique for a Puzzle game.
Notes
Since you only use two buttons to play, there are only two colours available per character, and those are the only buttons you will use to select characters. Also the characters in this guide are organized by the order they can be selected through Easy Select for convinience.
Also, even though I mention scrolling down from specific characters, you can also just scroll left or right to find the remaining ones afterwards, i.e – if you highlight Devilot, just scroll right to find Akuma/Gouki and Dan
Devilot de DeathSatan IX
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For Easy Select: Press Down from Morrigan
Akuma/Gouki
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For Easy Select: Press Down from Hsien-Ko/Lei Lei
Dan Hibiki
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For Easy Select: Scroll down from Donovan