Here is the full list of all 2230 Oik Memory 2 achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Pass the any timed level
Pass the level 8!
Open level 9
Pass the level 9!
Open all levels
Pass the level 7!
Open level 8
Pass the level 6!
Open level 7
Pass the level 5!
Open level 6
Pass the level 4!
Open level 5
Pass the level 3!
Open level 4
Pass the level 2!
Open level 3
Pass the level 1!
Open level 2
Pass the level 0!
Open level 1
Pass the level 然!
Open level 0
Pass the level 惘!
Open level 然
Pass the level 已!
Open level 惘
Pass the level 时!
Open level 已
Pass the level 当!
Open level 时
Pass the level 是!
Open level 当
Pass the level 只!
Open level 是
Pass the level 忆!
Open level 只
Pass the level 追!
Open level 忆
Pass the level 成!
Open level 追
Pass the level 待!
Open level 成
Pass the level 可!
Open level 待
Pass the level 情!
Open level 可
Pass the level 此!
Open level 情
Pass the level Z!
Open level 此
Pass the level Y!
Open level Z
Pass the level X!
Open level Y