These are my personal favourite series to play, and one of them I've been playing for over 20 years. I haven't bought every single game in these series, although I have come close in some cases, at least for the PC versions, but they are the ones I have enjoyed the most over the years and have spent the most time playing.
This is the oldest of the three series, with the first game being released back in 1991. I purchased the original Civilization game both for the Commodore Amiga and for my first PC, a 386 - it was simply that good a game that it was worth buying again on a new platform.
The game was created by Sid Meier and it is a turn based strategy game, where you choose a starting civilisation and ruler - different ones have different advantages - and then develop that civilisation by expanding it, improving technology, building cities and quite possibly eliminating the competition. Your civilisation can start from the dawn of history, where turns take more years to complete, to the present day and beyond. Wonders of the World can be built, which convey benefits, and technology can progress into the near future.
There are different ways of achieving victory, such as by winning the space race and successfully launching a ship to Alpha Centauri or by conquering all the other civilizations. You can keep playing the game after victory has been achieved, for those who want to develop as much of the map as possible. All the games in the series worked on the same basic premise, but there were improvements to later games, with better graphics, more units, more buildings, more civilisation, more Wonders of the World and just simply more of everything.
Sid Meier's Civilization V: The Complete Edition [Online Game Code]The first instalment in The Elder Scrolls series, Arena, was released in 1994, and it was an open world fantasy role playing game, as were the later games in the main series, where players can, to a large extent, pick and choose where they go and what quests they participate in, although there are limitations depending on what has already been done, or not done. The games feature a main quest series, many other series for different factions, and lots of side quests too, with extensive lands, monsters, dungeons, cities and non-player characters to interact with - or kill. The open world setting means that no two games need be alike.
The three main games from Morrowind, the third in the series, onwards are notable for the user created additions to the games which greatly expand the already impressive amount of potential playing time and maintain interest in the games long after they were originally released, with massive mods such as Tamriel Rebuilt for Morrowind. Some limited modding was possible with Daggerfall at least, but this game lacked the tools provided by Bethesda in later entrants in the series.
The Elder Scrolls Online - PC/MacThis is the newest of the three series with the first instalment, Hitman: Codename 47, released in 2000. The "hero" of this series - more of an anti-hero really - is a genetically engineered professional assassin and not-so-subtle bald man dressed in suit with a barcode tattoo on the back of his head usually known as 47, Mr. 47 or Agent 47. The perspective of these games is generally over the shoulder, except when doing things such as using a sniper rifle, or crouching behind objects, and despite certain similarities with first person shooters, the games are rather less action oriented. There is no bouncing around all over the game area and only the occasional bit of approved climbing or jumping.
Currently, there are five games in the series with a sixth in development; Codename 47, Silent Assassin, Contracts, Blood Money and Absolution. The second game, Silent Assassin, introduced the concept of the Silent Assassin rating, which continued through the series, where the object is to kill your target(s) without being detected at all.
Hitman: Absolution [Online Game Code]


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