
What is a crossover point in fantasy fiction? What constitutes a crossover?

We all experience a crossover point, whether it’s a minute daily, a second in every hundred hours, or one afternoon in fifty years on earth. A crossover point is the rare moment that we move beyond a liminal space and enter briefly into an otherworldly realm.
A crossover point is the rare moment that we move beyond a liminal space and enter briefly into an otherworldly realm...
This crossover event might occur at a specific location (a graveyard or a ‘haunted’ house, for example.) Or it might be at a specific moment in one’s life (a transition from one stage to another, perhaps a ‘big’ birthday or the eve of a significant event, e.g. a wedding day); or it maybe a combination of these.
This is why grotesque gargoyles guard the entrances to ancient churches… they function as threshold bosses. This is why 'significant events have lots of curious traditions and superstitions. And this is perhaps why non-religious attendees to religious ceremonies, such as weddings or funerals, feel uncomfortable… they feel wary because they sense an upcoming transition to another realm.
This why liminal spirits are said to ‘guard’ crossover places (such as burial mounds.) This is why going back to an old school or re-visiting the home you grew-up in feels curiously strange…it’s because you are re-living the moment of transition… you are re-living the crossover that you once experienced, the crossover from one state-of-being to another.

Consequently, this is why Halloween is celebrated internationally. Late October feels eerie and surreal because our world shifts from summer’s light to winter’s darkness, so the season becomes a solemn time.
This is why there’s a sense of dread in late October. — when light gives way to darkness — it’s because this darker season foreshadows the undeniable truth that life always gives way to death!
It has long been believed that All Hallowtide is a time of transition when beings, possibly visitors from the ‘otherworld’, discover they can pass freely into our (typically) well-defended boundaries... to infiltrate our earthly realms.
What is a crossover point? It’s the place, or the moment, when we travel beyond the point of transition (across the liminal threshold) and momentarily enter into an otherworldly realm.
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