A couple of days ago, Mass Effect 3’s “From Ashes” DLC was leaked via XBLA. Obviously, BioWare wasn’t prepared for such a leak and after a few days, the company decided to clarify why it was not included in the main game and reveal some more details about it. The content in From Ashes was developed by a separate team (after the core game was finished) and not completed until well after the main game went into certification. And that’s why the content was not included in the main game.
From Ashes includes the Prothean squad mate, an adventure on Eden Prime, a new weapon, and an alternate appearance for every squad mate. These alternate appearances are in addition to the ones already advertised in the CE.
Moreover, the Collectors Edition has been advertised from the beginning as containing a bonus character/mission, and that character was no other than the Prothean. BioWare simply didn’t feel the need to reveal him back then (and they had no reason to as it was a surprise).
The Prothean is optional content that is certainly designed to appeal to long-time fans, which is why he is part of the CE offering (the version many fans would be likely to purchase).
And start taking notes everyone: Mass Effect 3 is a complete – and a huge game – right out of the box. This character is additional and nothing more.
The Collectors Edition has been sold out in most places for some time now, and is becoming very hard to find (many players prefer not to purchase the digital version). As such, BioWare wanted to make this content available so that SE buyers could also incorporate the Prothean into their game.
The company promised to reveal some images and a video about this pack in the coming days.