That still leaves the problems of where magic and mythical critters like dragons came from. I'm betting they got magic the same way they got tools; by finding where we left it. There were probably old magic books thrown away because they were automatically assumed to be fake, when they were actually real. As for mythical creatures, they were probably "summoned" through magical effects, or maybe created through human science either before humans disappeared, or after by hidden human survivors. Maybe the mad science angle explains the rise of the ponies too. Edit: Fixed a typo where i typed 'whey' instead of way for some reason. following the "land after humans" idea, i think simple evolution could have get the "mythical" creatures done.As of now the only magical creatures are the ponies, right?