Portal

The game is designed to change the way players approach, manipulate, and surmise the possibilities in a given environment; similar to how Half-Life® 2's Gravity Gun innovated new ways to leverage an object in any given situation. Players must solve physical puzzles and challenges by opening portals to maneuvering objects, and themselves, through space.  Portal continues the proud tradition of Half-Life by showing rather than telling. Players aren't bombarded with tutorials or expository dialogue. Instead, they learn through experimentation. Early on, you are introduced to basic portal mechanics: walk through one portal, come out the other. Soon, you're handed the Portal Gun, which initially allows you to place only blue portals, while orange ones remain fixed in the environment. This gradual onboarding is brilliantly paced and perfectly teaches core mechanics without overwhelming the player.