Microsoft
At E3 2013, Microsoft announces a new alliance with Apple. They work together to ensure that SmartGlass is a great success. Smartglass takes off better than Microsoft had ever hoped. Even with Smartglass though, the 360 starts to die down as a result of the generation winding down.
On November 15th, 2013, the Nextbox releases at $299 (it's name is literally 'Nextbox') and sells amazingly. Microsoft offers a deal that gives away one free iPad 4 with every Nextbox sold. Suffice to say, Nextbox sales explode. Kinect 2.0 comes bundled inside the Nextbox for free. So, consumers get a Nextbox, Kinect 2.0, and an iPad 4 for free. Microsoft uses their monies to buy Activision, Ubisoft, and Take2. They recieve exclusive rights to Call of Duty, Grand Theft Auto, Assassin's Creed, and other big games.
On January 4th, 2014, Apple holds a press conference. During the conference, Apple announces the iPad 5. Surprisingly, Microsoft shows up and reveals that there will be another Nextbox bundle, this time with the iPad 5 instead of the iPad 4. Sales explode and the Nextbox sales during Jan-March are higher than they were during the holiday.
At E3 2014, Microsoft announces that the next three iPads (the iPad 6, 7, and 9), will be available only via Nextbox bundles. And they also announce that the iPad 6 would be releasing the next day. For the rest of the year, the Nextbox sells 45 million units. Who knows how they do during the next years.
Nintendo
Nintendo's Wii U was successful initially. It was tracking only slightly below the Wii and Nintendo was happy with sales. Even third parties were jumping on board. Unfortunately, that all changed when the Nextbox released. Microsoft paid off every third-party developer to put their games only on the Nextbox. Wii U is left with no third-party support.
As the Nextbox releases, consumers abandon the Wii U altogether, claiming the motion controls are like a poor man's kinect, and that the Gamepad was a poor man's Smartglass, and that the Pro Controller was a poor man's Nextbox controller. Nintendo recieves the unshakeable reputation as a shameless copier. The stigma is so strong that even Nintendo employees themselves believe that they are copiers.
As a result, most Nintendo employees are ashamed for their actions. To save any ounce of honor they had, they all perform public sudoku. The remaining Nintendo employees try to unite and compose themselves. Microsoft offered Nintendo to release their games on the Nextbox; they would be given more profit than they could imagine. But they deny the offer and the scattered remains of Nintendo leaves the gaming market altogether. On August 4th, 2014, Nintendo goes back to the playing-card business and makes a low, but moderate profit.
Sony
E3 2013. The PS3 is selling okay and Sony announces that they are happy with their first-party game's sales like The Last of Us. They see that the Nextbox looks to have a promising start, but they are not afraid. They announce the PS4 and say that it will release in 2014. Sony shows their first teaser for a PS4 game (Killzone 4). Audiences are blown away; many believe the trailer was fake and the PS4 wouldn't be powerful enough to run such graphics.
Winter 2013. With the Nextbox releasing, Sony slashes the PS3's price to $149. They seem to be highly confident that the price cut will keep the PS3 competitive for one more year. Unfortunately, the Nextbox is too strong and the PS3 sales fall. By the end of the year, the PS3 is seeing sales in the triple digits. Vita is dead.
E3 2014. The sales for the PS3 are so low that it begins to reach negative sales. Sony announces that they will be discontinuing the PS3 to avoid further harm. After seeing Microsoft's E3 presentation, they see that they cannot compete and announce that they will be canceling the PS4 too.
Sony leaves the gaming industry altogether and enters the drug industry. They have a decent start, offering high quality drugs for a low price. But eventually Sony grows overconfident and starts jacking their coccaine prices why higher than the competition. As a result, coccaine sales becomes so terrible that other divisions within Sony takes a hit. Sony has a press conference in the streets and assures consumers that their products are worth the higher price. But consumers don't agree. By the end of 2014, Sony implodes from within. Every memory of Sony is gone.
The Last Guardian is never released.