Since the release of the Season 3 Teasers, many Twilight Vectors have sprung up. I noticed that a few were already made before I could finish all the three poses... so I just made Twilight showing off her Skateboarding gracefulness.
You do realize that I made this 10 months before ~Equine-Bases made the base.
Looking at the details of the image at the side can go a long way: "Submitted on July 14, 2012" for me and ~Equine-Bases "Submitted on May 14" (which means it was in 2013).
So no, I do not have to give credit to ~Equine-Bases at all.
Though, thank you for bringing this to my attention. I checked how close the images resemble and it seems ~Equine-Bases used my vector to make the base. Here is the comparison: i.imgur.com/stUU3kv.png So maybe you could inform ~Equine-Bases to credit me instead, no? (fun fact: pretty much all of the bases ~Equine-Bases made, are made from other artists' works)