A bunch of classic games free on GOG. Syndicate in particular is one of my all time favourite games.
Syndicate is an isometric real-time tactical and strategic game. The game consists of a series of missions, in which the player controls a team of cybernetically modified agents attempting to take control of a particular country.
Syndicate Wars follows on from to the events in Syndicate, taking place 95 years later (in the year 2191).
Ultima Underworld is a first-person role-playing video game (RPG). Ultima Underworld has been cited as the first role-playing game to feature first-person action in a 3D environment, and it introduced technological innovations such as allowing the player to look up and down.
Ultima Underworld 2 is the sequel to Ultima Underworld the game is set in the Ultima fantasy universe. Players assume the role of the Avatar—the protagonist of the Ultima series—and adventure through multiple dimensions while seeking to prevent the evil Guardian from achieving world domination. Progression is largely nonlinear and the game allows for emergent gameplay.