Crossover — Tag Meaning
Brings two or more separate canons into contact: the detective meets the time traveler, the starship picks up a wizard, two unrelated casts discover they share a city. In a crossover both universes remain themselves — characters keep their own histories and rules, and the story's spark comes from worlds colliding rather than merging.
What to Expect From "Crossover" Fics
Characters from different fandoms genuinely interacting; half the fun is watching each cast react to the other's normal.
How to find Crossover fics on AO3
On AO3, click any tag to see every work that uses it, then refine with the "Filters" sidebar — combine it with your fandom or ship, set a rating, or exclude tags you don't want. See our AO3 filtering guide for the full walkthrough.
Browse "Crossover" works on AO3Want the deep dive? Read our full trope guide: Crossover →
Popular Fics Tagged "Crossover"
Real examples from AO3's most-kudosed works:
Whispers in Corners
by esama
Atlas
by etymologyplayground
snipers solve 99% of all problems
by silentwalrus
All Hallow's Eve - New York
by WhisperingDarkness
No Difference
by The_Bookkeeper
Road to Nowhere
by Aerugonian
Related Tags
Fusion
Merges canons instead of introducing them: one fandom's characters are poured into another fandom's world, replacing or becoming its inhabitants — the cast attends Hogwarts as students, pilots the Jaegers themselves, lives in the daemon-having universe natively. Unlike a crossover, the second canon's characters usually don't appear; only their world does.
Tag guide →
Crossovers & Fandom Fusions
The canonical umbrella that AO3's wranglers use to gather both traditions — worlds meeting and worlds merging — under one filterable roof. Browsing it surfaces the full spectrum, from cameo-sized crossovers to total fusions, which makes it the right entry point when you want multi-fandom work without committing to one mechanism.
Tag guide →
Crossover Pairings
Flags romance across fandom lines: a ship whose two halves come from different canons entirely. These pairings are usually born from 'they would be perfect together' lightning strikes or actor-shared casts, and the tag helps readers find them since relationship filters spanning two fandoms are otherwise hard to browse.
Tag guide →
Alternate Universe
The umbrella tag for any fic that changes the fundamental premise of canon, whether that means relocating characters to a coffee shop or rewriting the rules of their world entirely. AO3 wranglers treat it as the parent of hundreds of more specific 'Alternate Universe - X' subtags, so authors often apply it alongside a narrower variant or use it alone when their AU doesn't fit an established category.
Tag guide →
More Crossovers & Fusions Tags
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