Para openSUSE Tumbleweed execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/games/openSUSE_Tumbleweed/games.repo
zypper refresh
zypper install openrct2
Para 15.6 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/games/15.6/games.repo
zypper refresh
zypper install openrct2
Para 15.5 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/games/15.5/games.repo
zypper refresh
zypper install openrct2