Most of the Doodle God games are actually identical. Same episodes, same quests, same solutions, same file structure. So, yeah, missing 4th chapter is already in the game. You can enable it by replacing one file and adding one line of code. You'll need to download a free to play game Doodle God Blitz (it was used as a basis for Genesis Secrets). After that:

1) Go to ...\Steam\steamapps\common\Doodle God Blitz\data\aspect\1366x768\play_menu.

2) Copy the "tree_main_game.xml" file and paste it (yes, replace it) into the following folder: ...Steam\steamapps\common\Doodle God Genesis Secrets\data\aspect\1366x768\play_menu.

This has added Ch 4 and all DLCs to the Play menu. But you won't be able to access it, since it requires 200 elements out of 198. Let's fix that.

3) Go to ...\common\Doodle God Genesis Secrets\data\data

4) Open file "doodle_god.xml" with your Notepad.

5) You'll see all main quests there (in category <!-- MAIN -->). You'll need to delete the entire line and insert these two instead:


It has to look like this:

6) Save and quit.


This will enable the 4th chapter inside Doodle God Genesis Secrets. You are free to complete the last chapter.