Late for my updates! 
Number 43: Battlefield 2 (DICE, PC):
This is a truly important game in many ways, it exploded onto the competitive online scene and introduced/evolved a whole new way of thinking in multiplayer FPS, the aim here was to be tactical first and foremost and the usual running about trying to score frags was quite simply not a viable tactic. The different classes one could play and the multitude of weapons and gear also had a profound impact by presenting never before seen depth to the gameplay.
This game was both a commercial success and a cult hit and is still played to this day, it even has dedicated servers, which after about a decade, is an honor reserved for only a select few titles every released; that is Starcraft, Diablo II and Counterstrike territory in scope right there.
The shooting mechanics were more advanded than other shooters and the addition of real-life vehicles and helicopters/airplanes as well as boats, really lifts the experience above and beyond anything else at the time, or even the vast majority today.
Besides this shift in focus; the game was also savagely fun to play and features on many "most addictive" lists that I've read in my time, and due to the immense impact this title had on me personally, I see almost every other online shooter as a pale and distant second to Battlefield 2, with only a handful of excpetions.
Number 42: Titanm Quest (Iron Lore, PC):
For a huge Diablo fan, it was hard coping with the fact that Blizzard seemed content with having a decade+ long wait for the next installment and even Lord of Destruction did get really old at some point. Cue Iron Lore Entertainment and their brilliant epic set in various locations across ancient Greece, Egypt and Asia. The gameplay was just as simple and addictive as Diablo II but the game was a lot more balanced, and it was vibrant and colorful and had a slightly deeper magic system as well as awesome summons.
The locations were fresh and beautifully rendered and there were three difficulties; normal, epic and legendary, with items being levelled and named for each setting, same as the enemies. Normal was a nice intro; epic is where it gets fun and legendary is where you had your ass beat really badly.
An expansion called Immortal Throne was also released and one more was planned, but Iron Lore and THQ ran into massive trouble down the line and the game had to stand on its own along with the one expansion pack.
To this day; this is the very best alternative to the Diablo series and many feel that Diablo III would have been better of learning a lot more from Titan Quest, I am also one of these people. If you haven't played Titan Quest but enjoy isometric hack & slash RPG's; GO GET IT NOW!
Hint for number 41:
This is one of my most played games in the early 90's and it was released on my chosen platform in 1990 by Virgin Interactive. It was a sidescroller that introduced a cool new concept to its genre by allowing mounts and it featured three playable characters. This title has had a modern remake but that was -part of the title of the game- by reviewers almost unanimously.
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