Ruins is the first stage of R-Type II or second stage of Super R-Type. The boss here is Subatomic.

Description

According to the now-defunct R-Type Official Website, this stage is said to take place inside a fortress belonging to the Bydo that was destroyed sometime during the First Bydo Mission.

Differences between the SNES and Arcade

The Arcade starts this as the 1st stage in the game while the SNES starts as the 2nd stage.