The new Darkin Raa'tul

So this just hit the pbe: https://www.youtube.com/watch?v=Rj28QZ5Oufo

New sound files that have a very "evil" feel, people think it's gangplank (again) but this sounds to evil and inhuman to be him;

In my humble opinion, combined with the above link, I believe this is a teaser for the next champ after Ekko, now I'm not one to believe random posts, but here is the thing: https://www.reddit.com/r/leagueoflegends/comments/35ns4p/plausible_ekko_ability_leak/

This was posted before the Ekko ability release, sure it's not right, but from the Ekko Q&A it was right at a certain point during production, leading me to believe this person had real knowledge about the production pipeline...

So with all the info we have: A) Ekko leak saying after him is someone with a beast summon ulti B) Dude most likely right about Gangplank VU (oficial by Riot as next big thing) speaks of new champ in some detail, also mentioning a beast summon ulti C) evil laugh on PBE that COULD sound like Aatrox

PS: People are mentioning the laugh sounds like it's underwater, again I don't think that means gangplank, but I'll leave ya with a question, the Leaker said Raa'tul is related to Varus, how did Varus gain his powers?

What do you guys think? Do you believe this theory? Share your ideas and speculation!