by Q1 2015 I mean Jan, Feb, or March release date.

by "biggest" i choose to specify the criteria of sales.

digital games not considered because we can't even pretend to track sales.

re-releases not considered (like DMC or boarderlands handsome edition)

my list of contenders:

A) mario party 10

B) the order 1886

C) evolve

D) bloodborne

E) battlefield hardline

F) dying light

The Order 1886 and Majora's Mask

Battlefield: Hardline, then Bloodborne, then Evolve, then The Order 1886.

Bloodborne.

i vote the order 1886. despite all the haters i think this is going to surprise people. people have called it a "gears of war clone" and i think they are right to an extent,... it will clone gears success and be massive and the first true "next gen" title.

Bloodborne no doubt

Wait, sales then battlefield

I'm going to have a stab at Evolve purely because it's a multiplat which strikes the right notes to have mass appeal on PC/XB1 and PS4.

I'd probably expect Battlefield to be next up.

As amazing as The Order looks, I think it's going to disappoint saleswise as it will have the orange diamond of death on the packaging. I think Bloodborne will exceed expectations for Sony, but those expectations will be a lot lower than what the general gaming internet thinks they are.

crap,  that reminds me i wasn't going to consider re-releases.  updated OP.

Anything other than Battlefield Hardline is incorrect ...

Second place is either going to The Order: 1886 or Dying Light ...

Why are people going for Bloodborne when the OP clearly talks about sales? No-one is seriously expecting that game to beat a multiplat AAA franchise like Battlefield, surely.