Rapid Slash, Spiral Swords (hold L), s.H, f.H, Trick Down, f.H, release Round Trip, c.H, qcf.L (hold L), c.H, f.H, Trick Down, s.HSH, release Round Trip. c.H, qcf.L, c.H
You build the full bar back from Spiral Swords with this. It looks complicated, but it becomes intuitive after you do it a few times. I got the hang of it by practicing it starting from the s.HSH point, and then doing it from the start. Combos are often easier if you start practicing them at the midway point to get the inputs down.
How you end the combo after c.H is primarily a matter of meter and your opponent's health. If you want to kill and he has 200K+ left over, c.H, Spiral Swords loops. If you want to kill and he has 100K left, Lunar Phase, df.H, Dimension Slash. If there's a lot of life left and you don't have meter to kill, either Lunar Phase, df.H, air throw, or f.H, call an assist, Trick Down, or f.H, release Round Trip. Vergil is an extremely formulaic character.
damn, same problem with all vergils combos. Linking that stupid last cr.H after s.HSH. The timing is never the same. I'll continue practicing it, but i just wanna say I hate this dudes combos.