BS-03 is the third boss from Raiden III.
The BS-03 is a red submarine. Once it emerges from the water it starts shooting at the player and release floating drones which scatter bullets when destroyed. The boss is equipped with lots of guns on the prow, all of which must be destroyed. Once the guns are taken out, the boss will draw his main cannon and start sweeping the screen with bullets. Gunboats will also constantly come from the sides. Once the cannon is destroyed the boss will use two exhauster on the back to attack, eventually opening four extra guns to add to it's firepower.
|Raiden||Desert Spider - Flying Fox - Phalanx MK-III - Gijido - Land Crown - Guardian - Antonov Ma-27 - Doreineji Core|
|Raiden II/DX||Grand Crawler - Death Walkers - Albatross - Battle Axe - Thunder Fortress - Black Bird - Graphite - Huge Satellite - Mother Haven - Gray Nodule|
|Raiden III||BS-01 - BS-02 - BS-03 - BS-04 - BS-05 - BS-06 - BS-07|
|Raiden IV||Exerey Iss - Ordo, Fulas and Mairazard - Famel Ya - Aguen and Ewat - Da Rutura - Isdogaram - Horda Gardia - Horda Gestorada|
|Raiden V||Platon - Great Horn - Kraken - Spice Birds - Blow of Hornet - Messiah - Angel - Humpty Dumpty - Divine Rampart|