The Witcher 3 works as a feature topic because its combat, contracts and open world are tied to choices whose consequences reach beyond a single quest reward.
League of Legends keeps changing around a stable objective: five-player teams still have to turn lane and map advantages into the destruction of the opposing Nexus.
Skyrim is a useful example of a game becoming a platform: the base RPG, official expansions, Creation Club material and community Creations now sit in the same long-lived ecosystem.
Red Dead Redemption has persisted because Rockstar has kept the original game's story and open-world structure available across newer hardware rather than replacing it with Red Dead Redemption 2.
Black Flag became memorable because sailing, crew life and naval combat created a fantasy strong enough to stand beside the series' usual stealth identity.
Fallout keeps changing its format while returning to the same tension between exploration, character choice, scavenging and a world rebuilt from the remains of an earlier one.
Diablo's long-running trick is to make character growth readable through repeated combat, loot and skill decisions while changing the scale around that loop.