BTVS (post-Chosen) - Harry Potter (epilogue compliant) - Sherlock BBC (pre-Reichenbach)

DI Greg Lestrade is the result of a brief fling between Buffy Summers and one of the Lestrange brothers (she prefers older bad boy types, has a tendency to mangle names, and wanted her child to have his father's last name). He grew up with the Scoobies (explains how he deals with Sherlock so well) and decided to learn Wiccan magic rather than wand magic, so he didn't bother with Hogwarts.

When Lily Luna Potter was 10 years old, Ginny got pregnant again (remember, wizards can live quite a w...

BTVS/Sherlock (BBC) crossover preferably.

Ten years post-NFA: Willow, Xander, and Dawn are the only members of the Scoobies/Angel Inc left alive. They find themselves in the remains of the old Watcher's Council building. Willow uses the last of her life/energy/magic to send Xander and Dawn to a new world. They arrive in that exact location, but in an alternate universe: Mycroft Holmes's office.

Eventually, the main point of this crossover would be to see a (more or less friendly) face-off between Sherlock Holmes and Xander Harris. Sherlock!Scan meets The-One-Who-Sees.
...

Fact: The Kalderash Clan from BTVS lives in Romania. There are still living members, according to cannon.
Fact: G. Callen was born in Romania; possibly fathered by a Romanian man, but definitely the grandson of a "Roma girl".

Challenge: Someone from the second season of BTVS (Buffy, Xander, Willow, Giles, Oz, Dawn w/ her implanted memories) joins the NCIS: Los Angeles crew. He or she somehow (notices quirks, recognizes a particular accent while he's speaking Romanian, etc) realizes that G. Callen is actually a son of the Kalderash Clan (whether that's through his unknown father or...

I've seen the stories/challenges where Brittany/Santana/Quinn/Rachel/etc are Called as Slayers. Here's a different take: Lauren Zizes, McKinley High's biggest bad@$$, becomes a Slayer. How does she handle her competitions? Her increased appetite? Her boyfriend?

I would like to see a story set any time post-Season 1 of Glee; Season 7 of BTVS. Lauren and Puck are dating (still or again - your choice) when she wakes up both stronger and faster. One of the senior Slayers (I would prefer Faith, but Rona, Chao-Ann, or Kennedy would work too) shows up in Lima to explain what's going on and t...

Coach Shannon Beiste has noticed the oddities at William McKinley High in Lima, Ohio. They remind her of another high school - the one she graduated from nine years before it blew up. While looking through her deceased cousin's old yearbook, she comes across a picture of a young blonde being named Class Protector, and she remembers the stories Larry told just before he died, of Buffy Summers and her friends, and what they did for the town. She looks the group up online and finds that they have become the leaders of a world-wide collection of schools and learning centers.

Xander uses h...

Criminal Minds, Season 1 finale: The first two potential suspects are named Harris and Giles. The team are told to 'save her' and that the 'youngest holds the key'. My first thought was of the Scoobies.

So let's change things up. In this, Harris and Giles are names specifically chosen to bring the attention of the FBI to the Scoobies. While Reid did receive a skeleton key, what the note meant was that Dawn, the Key, was needed to help solve the case, as the victim(s) are drugged slayers.

I would like at least one member of the BAU team to already have some knowledge of the su...

"Why We Fight", an episode in season 5 of "Angel", introduced Sam Lawson, the only vampire Angel turned post-soul, making him the only vampire to ever retain a fragment of soul during the turning process. They could have really gone somewhere with that idea, but instead chose to dust him at the end of the ep.

My challenge to you is this: write a story centered around Sam and how that fragment of soul effected him all of his unlife. There are 60+ unaccounted-for years between his turning and staking. Is he the original inspiration for Blair Sandburg's thesis? Is he the subject of one o...

Dawn is the Key. As such, her true history (and the extent of the monks' memory spell) is unknown. I'd like to see a fanfic where she is somehow related to Neal Caffrey of White Collar. The connection can be as siblings, cousins, aunt/uncle and niece/nephew, or parent/child. Bonus points if you can come up with a logical way for Dawn to be the parent. I would like Mozzie to already know about the connection, and for Peter and Elizabeth Burke to make an appearance, though the actual point in the White Collar time line is up to you: before Kate, before capture, in prison, season 1, season 2, etc...

Pick a time in the Buffy/Angel universe where someone spent time as a patient in a mental hospital. Now, imagine that they meet some interesting people who are also not what they seem. How do they meet? How long are they both there? Do they break out together? Do they each secretly (or not so secretly) think the other really is crazy?

This needs to have a cross involving someone else in a place like that. For example:
-Charmed, when their house was a hospital
-Stargate SG1 when they think Daniel has gone crazy
-X-Men Evolution before Mystique got Wanda out

Must ha...

Samuel Summers hated growing up under his big sister's shadow. The slayer was bossy and annoying, and he knew it was her fault that he kept getting kidnapped. After the collapse of Sunnydale the 'family' moves to Newburgh Heights (or any other town near Cleveland - make one up if you want), Ohio.

When she was six months old, and demon killed Dawn Winchester's mother in a house fire. Since then her family has traveled all over America killing evil things. Now Dad is missing and the search takes Dawn and her brother Dean through the town near Cleveland.

It is your choice whethe...

Sam Winchester and Dawn Summers are twins. They meet up some time in their twenties. You get to decide how they were separated and how they meet up. Have fun.