The physical perfection of Margulis's swordsmanship is beyond doubt. His fights have been more like executions, with his blade unerringly finding the mark with every single strike. But what more can you expect? Margulis is well beyond the nominal challenge that Middles can offer him. What's left in his way but a little girl wtih a sword? Haha. The Falcon Style of Fencing is reliant on overwhelming an opponent with a quick rush, a tactic of no use against someone as tough as the Inquisitor. (Super note: I think that's Margulis's title, doublecheck this). Attacking a single target is all well and good, but what will Valeria do when Margulis clones himself and strikes at Valeria from all angles at once? Not much, as she'll be too dead to admire the superior talent that Margulis was blessed with.
