DOOM 3

Back in 2004, this game along with Far Cry and Half-Life 2 introduced gamers to the next generation of shooters. Doom 3 tells the story of a marine assigned to the research facility on Mars. The usual day at the facility goes terribly wrong due to the sabotage and all hell literally broke loose. The game utilizes the idTech 4 engine which was the top-notch game engine at the time. Unlike previous games in the series, this one leans towards horror rather than classic FPS. There is even a survival element as you'll often running around in search of ammo and armor plates. But the most memorable thing in the game is a flashlight. The thing is you can operate with only one item. You have a flashlight by default and any other weapon you've salvaged. You can either throw light on dark corners or shoot in the darkness. This is quite troublesome and exciting at the same time. Especially when your flashlight found a silhouette of a rage-induced imp coming your way. Well, you can beat it with the flashlight itself but it gives minimum damage. There are a lot of maps inside and outside the facility with entertaining voice records that tells the story of what was happening in this place. Of course, there are cheat codes for armor, ammo, weapon, etc. But it's more exciting to get each piece of weaponry procedurally as it was scripted by id Software developers. There is a rerelease called the BFG edition where you can use a weapon and flashlight simultaneously. But it reduces the tension and fun part so it's highly recommended to buy the original Doom 3.