Research and Development utilizes similar puzzles as those seen in between the shooter gameplay in Half-Life 2, but turns them into an entire game. The player must solve puzzles to traverse the levels, to the point where the game resembles a point-and-click adventure. The mod takes place in the Half-Life universe, but strips the player of their weapons, giving them only a Gravity Gun and antlion bait. A screenshot showing a vehicle the player must build to complete the game.
