You will need lots of firepower. Dynamite is more efficient to make, taking into account the resources, and how far down it gets you. Also, plenty of the green speed drinks for the lower part.

It's a bit of a grind to build up enough, but one way to help is to find the save file, and back up the game before making a "yolo" attempt, and depleting your supply.

How you do that
- Close the game
- is open the registry editor. (regedit)
- locate HKEY_CURRENT_USER\Software\Berezka Games\Mad Digger
- Save the entire folder as a .reg file
- To restore, double click the .reg file and it asks if you want to add it to the registry, and click yes
- Then you can try, and restore if necessary instead of grinding 100 more times.

https://youtu.be/pcCQWpuDmVo