Deus Ex vs Planetside 2
Deus Ex
Deus Ex is the first game in the Deus Ex game series which has risen to fame and had gained a massive somewhat-cult following due to its second sequel. The game is incredibly old-school and hence, its graphics may put a lot of players off, but the game offers an immersively detailed storyline that is set in a rather chaotic year of 2052. You even get to play as a super-cool cyborg who has many amazing augments, skills and weapons at his disposal. The game is not all shoot and kill though. It also has many ways for you to avoid bloody confrontation, which frankly will definitely delight players who enjoy having alternative approaches to an encounter.Unlike many other games that adds in fantastical elements to enhance its gameplay, Deus Ex is a game that emphasize on the possible problems and issues that a futuristic human world may experience. It deals in conspiracy and the human nature rather than fantasy and that's what made the game incredibly unique back in the day (and this statement is also relevant until today).
Planetside 2
Planetside 2 is a sci-fi-themed MMOFPS game that's the explosive sequel to its predecessor, Planetside, which was released back in 2003. In a way, the game is more inclined towards the extravagant and yet is still rather down-to-earth mainly because it features massive battlefields where hundreds to even thousands of players can battle it out for their faction. In fact, the game has an exciting gameplay which may bring to mind the games in the Battlefield franchise albeit the futuristic sort.Not to mention, Planetside 2 has an actual war playing out on the map where players who won a certain battlefield will essentially "claim" the land for their faction. The tug-of-war-like power struggle between factions help to bond the players in a way that resembles the deep rift between the Alliance and the Horde in World of Warcraft. The game is also developed by Daybreak Games which is in pretty good company along the likes of EverQuest 2, DC Universe Online and Lord of the Rings Online.
So, if you're looking for an epic MMOFPS game to fully immerse yourself in, then Planetside 2 is your best bet. If not, there are plenty of other casual shooters out there, but you can definitely expect that none of them can measure up to the faction-vs-faction tension, which usually erupts into another battle, offered in this game.