This is DMC5 Dante so I can use everything. This isn't DMC5 Dante so half of what I said is irrelevant.
Sparda is known as the best swordmaster in hell, etc, etc. The guy was so good and so amazing he could fight a whole army and the big bad. He had 2 apprentices and he teached them his own style and all that, they have been honing their skills for the past 2000 years, we will come back to them later.
Dante and Vergil were taught by Sparda when they were kids.
Gilver, is a puppet, an armor made with the combat date of Sparda, Dante and Vergil, the guy is a master who gave Dante a ton of trouble but he observed and analyzed him and learned how to trade blows with him even when being weaker and slower, there are even points that his skill overwhelms Gilver and he only survives cuz bigger dura. Mind you this is a Dante who just remembered everything and wasn't using anything skill related in years.
In DMC3 he fights Vergil (learned from Sparda) multiple times, a master on his own right and after a boost in power they were fighting in equal grounds with Dante eventually growing past him.
Later in DMC1 he fights Nelo, his skill with the sword had increased to the point he was the only real threat to Dante (besides Mundus) and even years after he remembers him as the most dangerous foe for that.
In the Anime he fights the 2 guys Sparda was teaching as he wanted to fight someone who had learned his father's style and had been getting better for the last 2000 years, Dante destroyed him casually after taking the battle more seriously, immediately after destroyed the older of the apprentices (iirc he even mocked them for their style)
Now this is were it gets juicy, a seasoned Dante fights Chen, someone who had all of Sparda's power and more and a weapon that allows him to watch the future, past, present, etc. Not only that but he learned all of Sparda's skill by using said weapon and even after having the advange of being able to kinda precog Dante and all the skill of Sparda he was still lacking, in Dante's words it was a "soulless" fighting style which made him angry and proceeded to one shot him despite the clear gap in power (Earl level of skill wank I guess)
Then there is 4 where he is stated to have skills beyond his father and finally there is 5, Vergil comes back stronger that ever and they fight, fight and fight even more for 1 month... and Dante still has the edge over him defeating him in a fight in the ending of the game just before the credits.
