User blog comment:B214/Light Novel Volume 16 spoilers/@comment-5185939-20131020023649

So Euclid was somehow able to copy a Longinus as an artifical SG.

Question becomes, 'how?'

I don't mean the tech, I mean where would the power for the boosts come from? With Boosted Gear, it's suggested Issei's drawing on Ddraig's power for each boost, but still leaves the question about Euclid's Sacred Gear.