Gameplay
The core gameplay of Gradius IV remains relatively unchanged. However, several changes were made on the weapons system in the transition from Gradius III. First of all, the edit mode has been completely eliminated, as are the "Snake Option" (s.option), the "Reduce" shield type, and the seventh powerup category. The seventh powerup category was the one that was labeled "!" and would produce detrimental results, such as reducing the speed or eliminating the weapons of the ship.
In this game there are a total of six configurations, the first four of which are migrated from Gradius II. The two new configurations are as follows:
Configuration 5: The missile mode is a vertical mine that is released above and below the ship. After a short delay, the mines explode, yielding a large explosion. The double mode is the standard 45-degree angle split. The laser mode is a thin armor piercing round that can penetrate multiple enemies.
Configuration 6: The missile mode is the flying torpedo, which produces two missiles that fly forward in front of the ship. The double mode is the tailgun, seen in other configurations. The laser is the twin laser seen in Gradius III.
Starting a tradition that is continued in Gradius V, this game introduced an online-ranking system. After a player's game was over, a password was presented. This password, which was hashed scoring information, could be uploaded to a Konami website. This was only available in Japan, and was discontinued on August 27 of 1998. This was similarly done for the Gradius III and IV console release. Score recording was disabled approximately a year after its arcade brethren.
Read more about this topic: Gradius IV Fukkatsu