Warren Buffett of Berkshire Hathaway (NYSE:BRK-A)(NYSE:BRK-B). has made it clear he wants to make his empire bigger. But the "Wizard of Ohama" may pull a rabbit out of his hat bigger than we ever imagined.

The comment
At the most recent Berkshire Hathaway annual meeting, Buffett was asked about the $44 billion acquisition of Burlington Northern Santa Fe (BNSF) -- technically $34 billion if you exclude the debt BNSF had -- and why Buffett chose to issue stock in order to make the deal, rather than use cash or issue bonds.

It was a valid question. At the time, Berkshire Hathaway issued roughly 5.5% more stock in order to complete the deal. Buffett noted, in retrospect, "we probably shouldn't have used equity for BNSF." He instead suggested it likely would've been a better move to issue on more debt since interest rates both were -- and are -- so low.

And while Berkshire Hathaway has had a number of major acquisitions since BNSF, it still reigns as the biggest single deal Buffett has undertaken, and an incredibly good one too.

But the most surprising remark came from Buffett when he concluded his discussion on the massive deal by noting:

If we see a really good $50 billion deal, we'll figure out a way to do it, even if that requires debt.

The possible direction
Much speculation -- from those including myself -- has been made about what the next possible acquisition from Berkshire might be.

Buffett continuously says "we will always maintain supreme financial strength, operating with at least $20 billion of cash equivalents." At the end of 2013, there was $48 billion in cash and cash equivalents at Berkshire, it was easy to expect a $30 billion acquisition was within reason.

But when Buffett admits $50 billion is possible?

That throws a whole new spectrum of companies into the possibility.

If you'd like to get ambitious, a $50 billion threshold would mean giant companies like Costco (NASDAQ:COST) and Phillips 66 (NYSE:PSX) are within reason since their market capitalization stands at $51 billion and $45 billion, respectively. Knowing Berkshire owns stakes in both companies, it's not unreasonable to think they are possible takeout candidates.

Add in the fact Charlie Munger called Costco "unbelievable," at the same time Buffett compared it to one of his favorites in GEICO, it's easy to think Costco especially would be considered.

And while Berkshire now owns less Phillips 66 than it once did thanks to the exchange of its position into Phillips Specialty Products at the end of 2013, it's critical to see Buffett himself said, "I have long been impressed by the strength of the Phillips 66 business portfolio." 

But there are more than 50 companies in the United States alone to be added onto the list of possible targets by Buffett. 

The key takeaway
Just one year removed from the acquisition of BNSF Buffett said in 2010:

We will need both good performance from our current businesses and more major acquisitions. We're prepared. Our elephant gun has been reloaded, and my trigger finger is itchy.

Whenever Buffett pulls that magic trigger next, it may been the biggest bang of his career.

Patrick Morris owns shares of Berkshire Hathaway. The Motley Fool recommends Berkshire Hathaway and Costco Wholesale. The Motley Fool owns shares of Berkshire Hathaway and Costco Wholesale. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.