You are piloting a sub and trying to torpedo your enemy as many times as you can in the time allowed. You do not see your enemy nor does he see you except in the sonar, in fleeting occasional glances and in seeing where a torpedo came from.
Subs was produced by Atari in 1977.
Boot Hill is a shooter arcade game released by Midway in 1977. The game is a sequel to Western Gun (aka Gun Fight). It's a classic one or two-player western gunfight game. Each player uses a small joystick to move their cowboy up and down the play area, while a second, much larger joystick is used to aim the pistol and shoot - this larger stick also has a trigger button. The game's single goal is simply to shoot the other player, who is situated on the opposite side of the game area. Wagons and cacti litter the middle of the play area, providing temporary cover from the opponent's gunfire. These obstacles slowly disintegrate as they are shot.
Fisco 400 is a top down racing arcade game for four players. Each player controls a colored car with a steering wheel and gas pedal. Each track fits on a single screen but changes slightly during play. The cars gain points for traversing parts of a lap. Whoever has the most points when time runs out wins the game.
Hustle is a 1977 game by Gremlin on Blockade hardware that is effectively Snake except that the normal pellets are replaced with larger pieces containing various point values that you get if you touch the piece before it disappears. Multiple pieces may also appear at once. You have one life; the game ends either when you hit yourself/a boundary or run out of time (the operator is presumably able to change how much time you can play for).
Barricade is an overhead view maze arcade game released by RamTeK in 1976. Players move their blocks across the screen to create walls to try to surround their opponents and force them to crash into the walls or any block.
Gameplay is a variation of the snake genre, in which players compete by surrounding each other with lines of dominos. Players change direction via a set of four directional buttons representing up, down, right, and left respectively. A player loses when they hit a wall, their own dominos, or their opponent's, at which point all the dominos in their line "fall" down.
Sega Tracer released in 1976 as a compact version of its predecessor Bullet Mark. These early light gun games provided a bridge between electro-mechanical arcade and early video games.