The issue of the ‘1.5’ reputation plagues many a sequel, when audiences set their expectations so high that anything short of a giant leap forward will see the videogame considered a revision rather than an innovation by many. While developers and publishers are often quick to dismiss any such idea, Deep Silver isn’t so worried about this reputation being attached to the forthcoming Dead Island: Riptide. In fact, they positively encourage it.
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“We wanted to provide more ‘Dead Island’ to players relatively fast and also to continue the story where we had left off, so it made sense to use the same – but improved – engine as Dead Island. The core mechanics are the same and a lot of things are familiar.”
So, they kept the name, engine, core mechanics and are continuing the story of their previous game, but this Dead Island is NOT a sequel to the last Dead Island... wtf?
This isn't Dead Island 2, i'm sure a true sequel will be " Dead World " or something of that nature.
Seems more like an expansion(pack) of the current story, not a new story & maybe Deep Silver thinks a all brand new story will be Dead Island 2.