The Protosaber is technically the first Lightsaber. Using an external power-pak to power it as technology wasn’t as advanced at this point. This was linked to the weapon via a power cord, making mobility and and functionality an issue. Some were upgraded when technological advances were made but mostly they were abandoned and replaced with modern Lightsabers. 

I’ve been playing Fate/Grand Order since March… the Camelot chapter just got released and I love Bedivere. SPOILERS: in FGO, this Camelot is an AU timeline where Bedivere never threw Excalibur into the lake like the king requested and so messed everything up… Then he lives with guilt for like a thousand years and has to join your party and fight the remaining Round Table knights to fix things.

…And I hope Proto!Arthur comes to the game soon because I will ship that.