The game is a horizontal scrolling shooter in which you take control of a jetpack propelled space warrior who travels between parallel universes and worm holes (hence 4-D or 4 dimensions) throughout the game. By flying over the top of the play field, you end up in an alternate universe. You travel back and forth defeating enemies until you reach a boss creature. On some occasions a worm hole will appear in the middle of the play field and you are taken to even stranger worlds...

Acrobatic Dog-Fight or "Dog-Fight - Batten O'Hara no Sucharaka Kuuchuu-sen" in Japan is a side-scrolling shooter arcade game released by Technos in 1984, featuring "cute" cartoon graphics and gameplay similar to the 8-way scrolling of Time Pilot but differs from the Time Pilot in many respects. In Acrobatic Dog-Fight the playing field was limited with a ceiling and ground as well as an ultimate destination to navigate to. Acrobatic Dog-Fight also added two buttons, a secondary weapon and an eject button. Eject could be used at any time and made it possible to hijack enemy planes and continue flying them. If the pilot failed to hijack an enemy plane he would parachute to the ground where a standard plane waited nearby.

It's the 21st century and N.A.C., a feared terrorist group of the galaxy, threatens to destroy Earth. They've developed the super weapon "EL" that will blast away Earth's ozone layer. And they've threatened to use it! As the world's top jet fighter pilot, you're in command of the of the ultimate in combat aircraft - the "Freedom Fighter." Armed with the latest in new high-tech weaponry, you and your jet are Earth's only chance against the merciless N.A.C. Good luck!

The N.A.C., a terrorist organization, has built a leaser emitter - "EL" - that is causing a panic, as it is capable of destroying the Ozone layer. We need you to pilot the Freedom Fighter, an advanced aircraft that may be the only means we have to crush the enemy!

Ancient shoot-'em-up relying on old-fashioned principles of keeping the player busy. Graphic and sound are now dated.

Aero Blasters is a Shoot-'Em-Up game, developed by Inter State and published by Turbo Technologies, Inc.. It was released in 1990 for the Turbo Grafx, and is one the system's most popular Shmups.

Air Buster: Trouble Specialty Raid Unit a.k.a Aero Blasters: Trouble Specialty Raid Unit is a horizontally scrolling shoot 'em up arcade game released by Kaneko in 1990, licensed to Namco.

Story:
In the year 2021 a mysterious orbital space weapon appears and assaults the nations of the Earth. The players control the pilots Mike or Holly who are a part of the Trouble Speciality Raid Unit whose mission is to stop the invasion.

Gameplay:
Players choose between one of the two Blaster fighters through scrolling six stages. The Blaster fighters can equip one of seven weapons. The weapons include the Striker weapon which adds additional firepower through vertically aligned Options, the Reverse shot which fires two diagonal shots from the rear of the ship, the Six Way Shot which fires semi-automatic shots in six directions and the Homing Shot which tracks enemies all around the screen.

The other three weapons are Missile based which vary from Red straight-firing Rockets and Green Homing Missiles. There is also the Border item which surrounds the front of the ship, keeping it from crashing into foreground objects. The only other Items include Power-Ups which increase the ship's standard shot power and Bonus Points that appear in the sign of Dollar signs.

Fly, shoot, kill, destroy - one of many such games.

One of the best horizontal shooters out there! Has awesome graphics and perfect gameplay. It's not that difficult, but is still challenging enough. Way too good to be this old.

Air Zonk was an attempt to update the company's image via a modern, punkish character called Zonk, who bears a purposeful resemblance to the Turbo's caveman mascot, Bonk.

This rare title takes the Turbografx's prehistoric, platform-jumping mascot and incorporates him into a wild, quirky side-scrolling shooter. You can tell Zonk and his friends are from the future because they all wear sunglasses! Air Zonk features attractive, cartoonish graphics rendered with bright colors and huge sprites.

Air Zonk is generally fun but there are a few issues. While the bosses look terrific, they tend to consume most of the screen and their projectiles are awfully hard to avoid. If you're playing for score, you'd better keep an eye on it, because the second you lose that final life it disappears. Air Zonk's soundtrack is probably its best feature, pumping out some of the best tunes I've heard on this system.

Deep within enemy territory, your fellow countrymen are imprisoned. Only one man in the free world would dare attempt to save them. You, Stringfellow Hawke, commander of Airwolf. And yet, as you strap yourself into the cockpit of your supersonic jet copter, you know this is the most dangerous assignment you have ever flown.
Your mission is mapped out. Airwolf's heat-seeking missiles and superpowered machine guns are fired up, ready to blow the terrorists away. But can you evade enemy radar time after time? Can you sneak behind the enemy lines, find the captives and bring them to safety before you crash land or worse?
Headquarters knows that you have the skill and firepower it takes. You say you've got the guts... now prove it!

A side scrolling space shooter.
Are you bug enough?

A side - scrolling space shooter similar to R - Type.

The goddess Athena has been abducted by the Lord of the Underworld. Her father, the great god Zeus, searched for a brave warrior strong enough to save her. He chose a brave warrior who died with honor & courage on the battlefield. Zeus raised the warrior from the grave and granted him the power to morph into a powerful, holy beast in order to do battle against the unspeakable horrors of the Underworld.

Altered Beast is a 1-player sideways scrolling beat-em-up. The game begins with the player controlling the human form of the resurrected warrior. During the levels the warrior will be attacked by a number of flashing animals. Destroying these creatures will result in an orb being dropped. If the player picks up an orb, he will begin his transformation from human into 'Beast'. Once 3 orbs have been collected, the transformation is complete. In beast form the player's character is much faster and stronger than in the human form, and also has the ability to throw fireballs at the enemy. At the end of each stage, after the boss fight, the player's special powers are taken from him and he once again reverts to human form.

The action in Altered Beast is untypically slow-paced and sedate for a game of this nature, but the game's premise and graphical flair helped to separate it from other rivals of the genre.

Alex and Stella from "Alex Kidd" are declared dead in the first stage of this game (Alex and Stella stones).

The small tail swinging gryphon that appears often in this game makes a comeback in "Golden Axe".

Andro Dunos is a horizontally scrolling shoot 'em up arcade game. The players are put in control of the Neo Type fighters designed by Earth's defense system and sent to end a long lasting war against an alien race. The ships are capable of selecting and upgrading four different types of weapons all ready available and categorized by attack: Shot, Bomb, Missile and Unit.

A side scrolling helicopter shooter.
Fly your comrades to safety and become a hero!

You, as agent Captain Blitztek, have to find a way through enemy territory to prevent the Axtoatles from taking control of the world. The mission will be aborted if the defenders inflict more than nine damage points on you. A game point system has been devised to further measure your skills as a navigator and survivor.

SciFi shoot em up.

Perky-looking female fighter jock takes on the space aliens from hell all by her lonesome.

A pathetically bad space shoot 'em up. The only thing good about it is the 15-second cinema during the game demo. Smacks strongly of a Konami or Irem shooter, but not as fully developed.

A horizontal shoot 'em up.

Earth colony Terra-12 is under the iron control of its recent alien conquerors. The colonists' only hope lies with one power-suited hero - Atomic Robo-kid!

An R-Type clone that has the same graphics style, but also has irritating sound and unimpressive gameplay.

Atomic Robo-Kid is a horizontally scrolling shoot 'em up arcade game released by UPL in 1986.

Story:
In the 21st century, a blast of cosmic radiation bombarded Terra-12, a deep-space outpost of Earth, hideously mutating all transplanted life. A fleet of savage beings followed the radiation wave and invaded the planet, and began the systematic destruction of all remaining sentient life. Years of battling the alien 'governors' have gone by, and now only one hope survives to avenge the desperate terran colonists.

Gameplay:
The player controls the titular character through six stages of increasing difficulty, facing an alien "governor" boss at the end of each level, followed by a "duel" level against other Robo-Kid sized robots. Many levels branch into others, giving the player the choice over which zone to enter next, increasing playability.

In the 21st century, a blast of cosmic radiation bombarded Terra-12, a deep-space outpost of Earth, hideously mutating all transplanted life. A fleet of savage beings followed the radiation wave and invaded the planet, and began the systematic destruction of all remaining sentient life. Years of battling the alien 'governors' have gone by, and now only one hope survives to avenge the desperate terran colonists.

You are that hope! Atomic Robo Kid.

Atomic Runner is a young scientist turned superhero thanks to his power armor, which he must use in an all-out struggle with an invading alien army that has managed to take him captive. First he must bust out of jail, and then it's time to lock and load. Go figure.

Decent enough port of a less-than-satisfactory arcade game. The characters are way too small, and the crappy gameplay is preserved perfectly. The sound is even worse than the pathetic mix used in the original. Consider a version for another platform before this one.

A standard shoot'em up.

Baltron is basically a horizontal Galaga. You scroll down the side and shoot at anything you see! One difference is that as you shoot, you also drop an item that can hits other ships. Use this to your advantage!