The Arias Protocol mod for Half-Life 2

The Arias Protocol is a first person total conversion mod for Half Life 2 (single-player only), which aims to combine action and stealth to allow the player to choose whether to sneak around, or just shoot everyone (or combine the two). For the former, they will have an array of gadgets, some of which can be used as weapons. For the latter, the player will have a large arsenal of weapons to choose from.

Story:

In early 2008, the US discovered a rare, highly resonant molecular compound, which they codenamed ARIAS. They found that it could be used to generate enormous amounts of power and, due to its efficiency, were able to save billions. Several weeks later, US satellites discovered large amounts of the compound buried in five African countries: Gambia, Senegal, Algeria, Mali, and Mauritania. These countries joined to form the North African Coalition, and began exporting the compound to the US, through a large shipping company called Africa International. The US, in return, provided the NAC with immense funding and military supplies.
Soon after this, a Nigerian terrorist organization began bombing NAC refineries that are processing the compound. Almost immediately, the NAC retaliated, launching a war to eradicate the terrorists. After several years, the bombings grew less frequent, and the NAC believed it had almost reached its goal. But then, a small shipment of the compound went missing, and the NAC intercepted a message sent by the terrorist group to the US: "Withdrawal all troops from foreign countries within six months or face the consequences. You have one week to respond."
Now, the NAC must determine where the terrorists have taken the compound, and retrieve it before it's too late.

For more information, check our website: Arias.hl2files.com