Starships riding fire across the sky. Heroes and villains exchanging laser fire. Desperate spacers struggling against an alien monstrosity. Vast alien vistas, flying cities, moonscapes, mad robots, and first encounters. In short: high-action science-fiction adventure that stimulates your sense of wonder. Cepheus Light puts you in the shoes of an adventurer visiting distant stars and encountering untold alien wonders. Whether you are a seasoned player looking for a rules-light game, or a new gamer wanting to experience what science-fiction role-playing games are all about, Cepheus Light: Upgraded opens your way forward. Cepheus Light: Upgraded is a set of rules for playing classic science fiction games. It includes rules on creating characters, resolving actions, fighting other creatures, and engaging in space battles, generating worlds, handling the risks of interstellar speculative trading, exploring new worlds, and many other activities. While rules-light and designed for fast, action-packed play rather than an accurate simulation of reality, Cepheus Light: Upgraded encompasses a wide variety of rules and materials for building a science-fiction universe and playing in it. Cepheus Light: Upgraded draws its inspiration from old-school science-fiction roleplaying games. It shares a lot of similarities with these games. Material from older rules sets and those created with Cepheus Light, the Cepheus Engine Core, and old-school sci-fi roleplaying games are easily compatible with only a moderate amount of adjustment. This is an update and upgrade of the original Cepheus Light rules, rebalanced and rewritten.