In The Deep the player takes the role of a ship which has to defend itself against a variety of underwater enemies, e.g. u-boats or jellyfish with weapons. All the enemies launch missiles or mines at the boat which can be dodged by moving left or right. Water bombs can be dropped to get rid of the enemies - but there are only eight available which slowly refill over time.
Sometimes a helicopter drops crates which include useful extras like smart bombs, steering rockets or additional speed. The ship can also turn into a submarine to collect things under the water. Every screen has a different objective, e.g. collecting an orb, bombing an underwater station or destroying a powerful ship.
Bat 'n Ball is a game that tests your reflexes as you attempt to guard a castle of sorts from a drug-crazed bouncing ball. You have at your disposal a crude but effective bat and (I assume) nerves of steel. Your castle is surrounded by a brick wall that crumbles whenever it gets hit by the malevolent ball. Defend it valiantly, for a hit to its core will lose you a life (bat). Stick around until your opponents lose their castles and you will progress to a new screen. Be careful - you have only three lives with which to brave the 20 screens and the last screen hides a nasty surprise!
Another Bomberman style action game. You have to place explosives on the ground and blast your way through the maze. Destroying all enemies is a good plan.
Froggy is a Frogger variant. The object is to get your frog across a road with traffic, then over a river of turtles and logs to one of five safety spots. In later levels, there is more traffic, snakes on the river bank and alligators in the river and, sometimes, in a safety spot. Once all five safety spots are filled, the game starts you at the next, harder level. There are four levels in total. After you beat the fourth level, you just replay that level until you run out of lives.
Firestorm is a top-down shooter, but the game requires a bit of thinking. The titular hero is able to create destructive fire-balls, control computer memory banks and move inanimate objects with the power of telekinesis. He must rescue his girlfriend, who is imprisoned in criminal organization's citadel. This citadel is a big maze, and the game has 12 levels.