This is an english 100% achievement guide since the only other guide is on russian. The game is fairly self explanatory and doesn't really need a guide but here it is to clarify and help get all the achievements.

Read this
you can just read the Quick guide just below to quickly get an idea on how to get all achievements
I've specified how the game works in the Game Modes section and what achievements you can get in the Achievements section to give a quick idea of the achievements.
Read this

there are 6 game modes in the Game. The only achievements are as follow. to lvl up to 30, which you get naturally. play all of the game modes once. and press every number and letter 180 and 120 times each. The fastest way is to play numbers for the number achievements and alphabet for the letters. The game mode Words might go a little quicker when it comes to amount of letters pressed but you won't be pressing some of the "more rare" letters like z,q,x and so on as much.

Achievements
There are 4 different kinds of achievements

• Start a game mode: simply start each game mode once
  
• Level achievements: reach level 30. you'll get this as you play
  
• Press numbers: simply press every number 180 times each. It's best to grind for these in the "numbers" gamemode
  
• Press letters: same as numbers but only 120 times for each letter. Its best to grind for these in the "alphabet" mode. "Words" mode can be ok aswell but you won't be pressing letters like z,q,x and such as much so, alphabet mode should be a bit better.

This section is to help with the different game modes
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First unlocked game mode


How to play: you simply press the specified number and keep pressing numbers until you cant hit anymore. I used my keypad as i found it faster and easier in this game mode. This is the best gamemode to unlock the number pressing achievements
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Unlocked at lvl 5

How to play: simply as in the numbers game mode press the letters the best you can. This is the best gamemode to unlock the press the letters achievements
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Unlocked at lvl 10

How to play: This is a new gamemode that weren't in slash it 1. You simply have to spell out the words the best you can and avoid the letters reaching the left edge of the screen. This gamemode can be ok to get the press the letters achievements but rarely shows letters like z,x,q and such, so alphabet mode should be better.
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Unlocked at lvl 15
How to play: The same as all other the previous game modes except the letters are more crazy and spin and fly around the screen more.
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Unlocked at lvl 20

How to play: The same as Insane Numbers but with letters.
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Unlocked at lvl 25

How to play: this is the last game mode of the game and is a combination of the Insane Alphabet and Numbers mode.

I hope the guide helped either clarify something or help you find out how to get the different achievements. let me know if you have questions or additions to the guide :D.