- For the original Earth counterpart, see Kyosuke Nanbu.
Beowulf is a Banpresto Original enemy character in the Original Generation saga. It is revealed his name is a code of the Shadow-Mirror counterpart of the original Kyosuke Nanbu. He pilots the Gespenst MK III, similar to the Original Generation universe Alt Eisen Riese, but blue in colour with some additional abilities such as regeneration capabilities and overpowered energy output. What's significantly different about this Kyosuke Nanbu is that he possesses some form of strength that can be said to be near demonic in nature, which is entirely opposite to the Original Generation universe Kyosuke's inhuman luck. Beowulf only appears in the prologue of Original Generation 2, where he leads his squad of Gespenst MK IIs, the Beowulves, to fight against the Shadow-Mirror's coup d'état.
During the shuttle incident involving Kyousuke and Excellen in the Shadow-Mirror world, Excellen died in the incident while Kyousuke was the one who the crashed Einst merged with, as opposed to the OG world. After being taken over by the Einst, he became a ruthless, sadistic man hell bent on destroying and rebuilding the world. He is also shown with Einst face markings, hinting that he might have been possessed by the Einsts, and speaks with a slow, dejected speech style.

Beowulf in Super Robot Wars OG The Inspector anime
In the Super Robot Wars OG: The Inspector anime, it is revealed that Kyosuke of the Shadow-Mirror universe murdered the universe's SRX Team in cold blood. In the very same anime, after Stern Neue Regisseur's defeat, Beowulf successfully made a jump to the OG universe and attempts to recreate that universe like he did with the Shadow Mirror, but the combination of the might of EFA and Axel Almer managed to kill him for good (despite Axel seemingly being killed in the process).
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