Pronouncing [i] like "eyi" has always been in my life, but I don't know who from I heard it so much. I finally found a person who actually speaks like this. It's Matthew Murphy, the vocalist of The Wombats. We can hear him saying "lyrically", "melancholy" and "musically" in 1:33 here: https://www.youtube.com/watch?v=hN85VXvsn0Y
Actually, I think there are accents where it's even more emphasised. But I think it can be heard only at the ends of words, words like "really", "creepy", "we".
What is Murphy's accent and what other accents have got this feature?