User blog comment:DarkCreeper/New Spooky laugh on PBE, what could it be?/@comment-3974211-20150608203619

The laugh sounds underwater and all bubbly, and for this to be the new Classic Gangplank would require changing his theme quite considerably (which we would have been told if they were). I suppose it could be a 1350 skin (i.e. that's new Classic Gangplank's laugh with Deep Sea's watery voice filter) - but it seems unlikely that a 1350 skin would get an in-game advertisement (and if they're advertising new Gangplank, they wouldn't use a version of his voice with a filter).

It's either a new champion or a legendary/ultimate Gangplank skin (e.g. Deep Sea Gangplank).

A new champion would suit the fact both Miss Fortune and Gangplank are getting upgraded at the same time - i.e. we're about to get a Bilgewater event (like how the Freljord event saw upgrades to Sejuani, Ashe, Trundle and ARAM at the same time as Lissandra's release, as it means all the champions can have quotes between each other).