This theme is looks cool and for those who like dark themes, it is related to Linux Mint But you can install it on Ubuntu/Linux Mint/Other Ubuntu based distributions. Dark-Mint is only available for GTK 3.4/3.6 and Cinnamon. Author released this theme in two versions for GTK and Cinnamon separately, but NoobsLab added both versions in one package.
1st: Download Wallpaper
2nd: Choose Icons from collection, You can use Gnome-tweak-tool or Ubuntu-Tweak to change themes. (To change Cinnamon theme, you need to go in cinnamon settings)
To install Dark-Mint theme on Ubuntu/Linux Mint open Terminal (Press Ctrl+Alt+T) and copy the following commands in the Terminal: