Simon Quartz is the penultimate boss from Raiden Fighters Jet.
Details
Simon Quartz appears as a large hovering tank. It has multiple guns around its body which constantly shower the screen with bullets but can be destroyed. Once the two turrets on the sides of the center cannon are taken out, the deck opens up, revealing six more guns on the inside. After the center cannon is destroyed, it will begin using more complex bullet patterns, along with being able to use the two smaller cannons alongside the rotating cannon they're behind.
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Concept art