Per wiki policy, Spoilers Off applies here and all spoilers are unmarked. You Have Been Warned.
The legend goes that long ago, a woman named Marion Marshall had the power to bind the Remnant Ark above Elysion (and others) and travel to the Sacred Lands. She also had an affair with the Imperator, among other things.
DMC 3 might just be some random retelling of what happened, with Lady— known in this legend as Mary Marshall— binding the Temen-Ni-Gru (the Remnant Ark, or should I say, Remnant Arkham) to serve as a medium between the regular town and the Demon World (the Sacred Lands). With her blood (Marion's Blessing), she bound the tower to be able to travel to and from the Demon World/Sacred Lands, and possibly seal some evil in a can. Over time the legend changed, and Mary was known as Mary Ann (Mary being her real name, Ann taken from Kalina Ann) and eventually Marion Marshall.
Vergil is the "Imperator" Mary had an affair with, or he with her over the Queen of Glenys, who is actually Alice from the manga. With Mary's power to bind Remnants pretty much in his possession, he changes his title from Imperator to God Emperor and starts razing a few towns. After finding out about said affair, and losing the kingdom to the God Emperor, Alice's hatred for him is so great that it spans ages, maybe hinting at who "The Ladies of Bloody Alice" really are. ....What? Don't look at me that way!
The only solution here, is that the entirety of Dante's story, what we're playing through, is something she made up to justify where exactly he was while she was grapple-hooking and biking her way everywhere in the most non-linear fashion available. It also explains the weird gaps in her location. There was no real way she could have gotten to the bottom of the tower at Mission 9 from her spot in Mission 7 which was with her Kalina Ann lodged into the side of the tower after somehow surviving a fall that should have killed her from the sudden stop (see: Gwen Stacy). She was too far down to climb up to where Dante was standing, and obviously too high up to finish her fall down. It is very likely she was sidetracked the old fashioned way and, while narrating the story to some hapless listener, made that part up.
Let's look at the rest of this story, shall we? Clowns? Hollywood-esque movie-magic action scenes? Her having survived all of these weird occurrences in the choppiest, weirdest, and as stated before, non-linear fashion possible? Clearly, we're dealing with a girl so upset over the loss of her mother that she's retelling an event six shades of silly as a form of escapism or to make herself feel better. At best, the tower isn't even as big, spacious, or weird as it seems in the game.
Alternately, Dante could have just told her his side of the story, which explains why she can narrate it to you, but then he falls into Unreliable Narrator status too. Really, kicking ass with a motorcycle? Demon swords that can talk? Being able to stop or slow down time, but somehow not having that ability ten years later (read: in DMC 1)? Clearly, we're dealing with a guy so upset over the loss of his mother (and brother) that he has to make himself look the regular Hollywood Badass Longcoat to make himself feel better.
- Or instead of being traumatized and trying to make up unbelievable stories to feel better, they're just regular boasting show-offs. Dante'd definatly be the type to make up the most incredible story for laughs, at least. If Lady did, I could imagine it be to reel in customers for better business if not just for showing off.
- This...makes PERFECT sense!
- As an added note, vampires of her kind are said to surface on either the anniversary of their death, or on the full moon. What do we see in Mission 8? The full moon needed for her to appear in the Opera House. Also, they tend to be attracted to poets and musicians. Dante is named after a poet. What does he do as soon as he attains Nevan as a guitar? Rock the fuck out. Out of nowhere, almost as if he were compelled to do it. She can work her magic very well.
- If we assume Arkham was already studying to become a demon when he met Lady's mother, Lady is obviously a part-blood. Her demonic heritage can't be as strong as Dante's or Vergil's, but it's still enough to explain her extraordinary speed, reflexes, aiming skills and recovery. The assumption makes sense, since I can't really see Arkham marrying, then aspiring to be a demon, then finding out that his wife is the descendent from the woman Sparda sacrificed. Plus I like the irony behind Lady forsaking and spitting on anything demonic, while her father's heritage might be the only reason she actually stood a chance against the dangers of Temen-ni-gru.
- Material Archive: Note of Naught, the DMC 3 artbook proves that Arkham, not Kalina Ann, is the one of Lady's parents descended from the priestess. She got her part-priestess blood through him, and he turned into a demon later on by sacrificing his perfectly normal wife.
According to the biblical story (possibly influenced by Etemenanki, "temple of the foundation of heaven and earth"), back when humans spoke one language and came to the land of Shinar (or just Mesopotamia if you want to be general about it), they resolved to build a city with a tower to connect Heaven and Earth, either as a monument to their God or just because, I forget which. God came down to see what they did and decided he couldn't let that happen, so he confused them all by separating them and their languages and making them unable to understand/interact with each other.
According to this story, humans wanted to build a tower connecting the Demon World (Arkham called it "Heaven" in the manga at one point) and Earth as a monument to Mundus/Evil. Sparda went over, decided he couldn't let that happen, and got to kicking some ass. He sealed the (Japanese) Seven Sins, stuck the (Greek) Cerberus in mission 3, the (Hindu) deities Agni and Rudra in mission 5, the (Irish) vampire Nevan in mission 8, the (Hebrew?) Leviathan . . . somewhere, the (Old English) Beowulf in Mission 11, the (also Greek) Geryon in mission 12, and so on and so forth. Point is, he split each boss demon into their own area so they wouldn't be able to interact with each other, scattered the humans, and stopped them from building the axis mundi by sealing the tower into the ground rather than just leaving the thing in ruins.
It's likely that in the DMC continuity, the story of the Tower of Babel was based on the actual event of Temen-ni-Gru being built and sealed, given how much alike◊ they both look.
- Confirmed, but for February 2020. The Switch port adds the ability to switch styles and weapons freely (like in later games) and a local co-op Bloody Palace where both players can work together as Dante and Vergil.