This is a thread where we can throw crossover story ideas that maybe somebody would actually write.
I'll start with mine:
What if when Sunset turned into a raging she-demon, she inadvertantly created a Nobody? And this Nobody was found by the Mane 6 before Organization XIII could? (This would of course be in Equestria)

Hmm... Well the only crossovers I would be good at would be Zelda.

4799180 Well I have two idea for crossovers involving O.C.s of Mine from Elder Scrolls Online and one that is a Mass Effect crossover using an O.C. from the Mass Effect Three multiplayer. One I already have up is a crossover with Dragon Age Origins using my human noble from the game.

4799514
Cool, lets hear them.

4799528 Well I'll start with the Mass Effect crossover then. In it an N-7 Shadow Infiltrator comes to Equestria after being sent to secure a Pre-Prothian artifact of unknown origin after the Reaper War ended. This artifact opens a portal when it is activated at the same time power magic is used in Equestria from some even I have yet to figure out and my the people on the other end are attacked by creatures from Equestria, changelings maybe I have't figured that out just yet either. Anyway to stop the creatures from coming through the portal my O.C. jumps through to try and stop them by engaging them in battle, naturally the portal slams shut during the battle leaving her stranded. That's all I have for the moment there are a lot of details I still need to work out.

The E.S.O. crossovers are much less defined. All I can say is that one idea I have involves my Breton Sorceress getting catapulted into Equestria after she defeats Molag Bal and reclaims her soul. The other is more or less a combined crossover with both E.S.O. and Destiny with both mine and my co-writer's O.C.s coming from each place. We haven't gotten any farther than that for right now.

Well this sucks. I don't play any 'M' rated games and Twilight Princes is the only 'T' rated game I've played from beginning to end.

4799596 Or it could be an intergalactic scenario where they simply go to the galaxy that the world of equestria is in. and they are still fighting the reapers and the ponies are also experiencing problems from the reapers and we help them. new allies!

I have several, but I would probably like to talk about the one involving Shin Megami Tensei:

Twilight Sparkle knows of her destiny as an alicorn, but she would have never fathomed that it would involve demons. When demons storm the once peaceful land of Equestria, she discovers that her ascended abilities allow her to tame demons. With her new abilities, status as a princess and newfound revelations on the foundation of Equestria, how will she impact the fate of an entire nation and world?

4816661 I have seen that done and don't want to go that route, it doesn't appeal to me. I'm not saying it's a bad idea, it's just not the direction I want to go in is all.

4817403 oh. Ok

4819270

I just thought of an Undertale crossover idea that stars Sunset. It takes place in an alternate universe where the Christmas Equestria Girls special comic went a little different. Instead of trying to prove herself, Sunset instead just runs away. She runs to a mountain cave where she accidentally trips and falls down a hole. A hole that leads to where monsters live. Now she must use all of her friendship skills to make some new friends, find a way out, and maybe even help end her new friends imprisonment. But a certain psychotic and murderous entity named Chara and a souless, and heartless, flower named Flowey seem to want to make things difficult for Sunset.

4850246 I've been having some vague thoughts about a Dragon Ball Xeoverse crossover starring my Time Patroler where she gets involved when someone tries (and I'm not saying who) to alter history and make Twilight lose her battle with Lord Tirek.