Raiden IV made its first location test that was held at Akihabara Hey in July 22-23 2006, on an Egret II system. Its version had 3 difficulties : Light, Original and Strong, as well as including the feature that the 1P has a plasma laser, while the 2P has a proton laser. The GROUND DOOR that opens to reveal the Level 1 boss consists of 'bushes' and 'roads'. Cutscenes are seen showing the first boss exploding, but, it does not show the second boss exploding, however.
The 2nd location test was held again at Hey and at Taito Game World in Shinjuku on October 14-16. The cutscenes showing the boss' destruction is nixed in this version.
The 3rd location test was held at High-Tech Sega in Shibuya and Taito Game World in Shinjuku on December 27th. In this version, the previous idea of having 1P having the plasma laser while 2P has the proton laser was nixed. Instead, players were able to select either plasma or proton laser to play through before starting the main game. 2nd Round for the game after 1st Round was completed is implemented.
The 4th and final location test was held at Shinjuku Gesen Mikado on February 20th 2007. In this version, Flash Shot System's multiplier is increased to 5.0x at maximum. Strong difficulty is nixed, however. The damage power of weapons are readjusted. Enemies that appeared during Stage 2's mid-boss were nixed.
MOSS, Ltd. launched Raiden IV arcade on June 7th 2007.
The boss from level 2 of "Raiden III
" makes its appearance as a regular enemy.