Since there is probably a lot of fanart and pictures with characters from multiple generations shown together, this is probably the best place to post it, and I'll start off with some MegTwil pics since they're one of the few from different generations that seem to work together.

Those are awesome artworks. They really should had done a cross over with Twilight and Megan.

Here is the rest of Megan with G4 and possibly G5, though I still think it was a missed opportunity to not adapt her for G4.

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So many cool artworks!

Here is what Danny and Molly would look like with G4 characters.

I just had to put in this one.

Even though Majesty was just a character from the G1 UK comics and the generations aren't even related, there are still a group of bronies who believe that she is the mother of the Royal Sisters despite there being no evidence supporting this.

Seeing that MLP Generations came out recently, it counts as a generation leap, though this comic series didn't do too well and even made G4 end in a bad way, plus part of the reason I get each of the issues was to finally see Megan actually interact with the G4 characters, but once again, I was given false hope on that just like all the other times I thought it would occur making it now feel like a lost opportunity.

Here is what the main cast from Rescue of Midnight Castle would look like with G4 animation.