A crucial plot point of CW's 'Legacies' is just how important the mysterious knife is to the supernaturals and the Salvatore School of the Young and the Gifted. There's a lot of questions surrounding the knife - is it good or evil? Is it something that will save the world? Why did Landon steal it in the first place? While we don't really know for sure, there are many possible theories as to what the knife is and its connection to Landon. However, a new theory suggests that it may not be about Landon at all.

Theories so far have suggested that Landon is a doppelganger of someone who existed even before the Mikaelsons, the first immortal Silas and the first Hunter Qetsiyah's time. The theory suggests that an evil supernatural creature that existed at the same time caused mayhem and a hero brought peace to the land by defeating the beast with the magical knife and locking him away in the Other Side. This evil creature is said to have used his minions to cause harm (dragons, gargoyles and massive spiders like the ones we've seen on the show so far on 'Legacies'). Landon could possibly be this fabled hero's doppelganger or be from his bloodline, explaining why the knife may have called out to him and why he was able to wield it. Some have also gone on to speculate that he may be a demi-God.  

However, a new theory suggests that the incidents with the knife may not have had to do much with Landon at all - it may be a way for the monsters to go back home to the Other Side.

The Other Side or the Dark Dimension is the purgatory for supernatural creatures in the show's universe. One fan speculated referring to the first creature who burnt down a bus full of people and was unable to communicate with Alaric Saltzman and Hope, "I think they are from the dark dimension that is featured in the original books. I think this because the dragon looked like she had lived there for a while but she also looked like she was out of time as well," the fan wrote. "I think that blade opened a door to another world and a bunch of new monsters came with it and I think it's happened in the past. Here's my theory:  the dragon was hiding and stranded on this world and recognized the knife instantly. She knew it was her ticket home and desperately wanted it."

'Legacies' which is a spin-off of 'The Originals' which is again a spin-off of 'The Vampire Diaries', is based on a series of books of the same name written by  L. J. Smith. The fan further said, "I was thinking more like whoever left the blade left the gargoyle to guard the gate so nobody could go to the Dark Dimension unauthorized." 

It is entirely possible that the spider and the dragon were dropped onto Earth after Landon picked up the knife, causing a breach in the dimension. The knife could be the only thing that they could use to go back to where they came from - but it could also mean that the creature could be unleashed in the process. 'Legacies' is definitely building up to a great war and fans are almost certain it will feature some other dimensions - after all, Julie Plec does love her dimension traveling as seen on both 'The Vampire Diaries' and 'The Originals'.