For openSUSE Tumbleweed run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:Bus-Babao/openSUSE_Tumbleweed/home:Bus-Babao.repo
zypper refresh
zypper install simutrans-extended
For openSUSE Slowroll run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:Bus-Babao/openSUSE_Slowroll/home:Bus-Babao.repo
zypper refresh
zypper install simutrans-extended
For 15.6 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:Bus-Babao/15.6/home:Bus-Babao.repo
zypper refresh
zypper install simutrans-extended
For 15.5 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:Bus-Babao/15.5/home:Bus-Babao.repo
zypper refresh
zypper install simutrans-extended