Voadam
Legend
Non D&D games played with my current group: World of Darkness (Vampire the Masquerade specifically) and Shadowrun. Mutants and Masterminds might and might not count as it is a d20 superhero game (with no hp).
Vampire is designed as a horror system. The horror primarily comes from the premise, as a vampire to survive you need to prey on people. Blood you get from people is also used to heal and to power a lot of vampire powers. Also there is the humanity mechanic with possible loss of control in specific situations (hunger, terror from fire or sunlight or holy stuff, and anger). There are a lot of themes of lies, control, being a monster, being a person, and being exploited in a crappy world. Some of the themes are supported by mechanics like dominate and presence powers and blood bonding for the control theme. In my opinion a lot more is determined by theme and set up, so the elder versus younger generation conflict, clan versus clan conflict, other supernaturals, the theme and tension of being part monster part human. It can be played as supernaturally powered people by night (such as by abstracting feeding including by using the herd rules), or intensely personal horror. Lots of options.
Vampire is designed as a horror system. The horror primarily comes from the premise, as a vampire to survive you need to prey on people. Blood you get from people is also used to heal and to power a lot of vampire powers. Also there is the humanity mechanic with possible loss of control in specific situations (hunger, terror from fire or sunlight or holy stuff, and anger). There are a lot of themes of lies, control, being a monster, being a person, and being exploited in a crappy world. Some of the themes are supported by mechanics like dominate and presence powers and blood bonding for the control theme. In my opinion a lot more is determined by theme and set up, so the elder versus younger generation conflict, clan versus clan conflict, other supernaturals, the theme and tension of being part monster part human. It can be played as supernaturally powered people by night (such as by abstracting feeding including by using the herd rules), or intensely personal horror. Lots of options.