lightdm-pantheon-greeter from X11:Pantheon project
Select Your Operating System
Add repository and install manually
For 16.0 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/X11:Pantheon/16.0/X11:Pantheon.repo zypper refresh zypper install lightdm-pantheon-greeter
For 15.6 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/X11:Pantheon/15.6/X11:Pantheon.repo zypper refresh zypper install lightdm-pantheon-greeter