Without these weapon upgrades defeating the gigantic end of stage bosses is exceptionally hard. Though the play mechanics vary little throughout the game, each stage looks different which helps to avoid monotony. In the Sega version you could even choose the order of the levels, allowing you greater flexibility to vary a play-through. This option is however missing on the Super Nintendo and it’s the first of many omissions.
Admittedly the level bosses are marginally larger and have more frames of animation, but far too often you are left staring at a four colour ship waiting for more enemies to fill the screen (then of course you have to endure the inevitable slow-down that comes with their arrival). There is a lingering sense that ‘Thunder Spirits’ was a rushed programming job, or one that was handled with a lack of expertise and knowledge of the Super Nintendo's inner workings. It should have been an impressive shooter – the optimal version of ‘Thunder Force III’ – instead it's rarely mentioned when people talk about the best shooting games for the SNES. It’s a game that didn't live up to its potential, or indeed the legacy that comes with a ‘Thunder’ title.