general the Alicorns are Planeswalkers. and the HASBRO SPARK.

[Evil Pink One 13,512]

in gen 5 Izzy can see ones sparkle..... what if it's the same spark a being experience in becoming a Planeswalker in MTG( MAGIC THE GATHERING.)

MLP and TRANSFORMERS have been presented in MTG, and them to each other. and transformers have their allspark.....

what if they're all in the same dimension.......

the alicorn princess retiring... just planeswalking to another realm....

maybe the same reason why twilight left... she became a Planeswalker and traveled to another dimension.