Metallurgical coal miners are still dropping like flies in a powerhouse of a consolidation cycle that shows no signs of quitting; unless, of course, it simply runs out of strategic targets.

International Coal (NYSE: ICO) became the crystal-clear target to watch within the met coal world after Alpha Natural Resources (NYSE: ANR) snatched up Massey Energy (NYSE: MEE) in January, and my readers will have already considered Arch Coal (NYSE: ACI) as a likely contender to acquire the International Coal's high-quality reserves base of 1.1 billion tons.

Arch offered a 32% premium over International's closing price from Friday with a bid of $14.60 cash per share. The $3.4 billion deal would transform Arch Coal into the second-largest met coal miner in the U.S. behind Alpha, and spawn a 47% explosion in Arch's pro forma 2011 met coal output, from 7.5 million tons to 11 million tons. By 2014, the addition of production from International's Tygart Valley No. 1 mine could bring pro forma capacity to 14 million tons per year.

Arch had already adopted a heavy emphasis upon growing access to the export-bound segment of the domestic coal market prior to this move. After all, global demand has fully emerged as the driving force behind growth in the domestic coal industry. The miner recently secured a 38% interest in a coal terminal in Washington -- where rival Peabody Energy (NYSE: BTU) has proposed construction of its own separate terminal -- in exchange for an equivalent 38% share of throughput capacity. Arch has secured export terminal capacity on the East Coast as well and recently reported a 60% increase in first-quarter export volumes over the prior-year period. John Eaves, Arch's chief operating officer, referred to "significant and growing access to high-growth seaborne metallurgical and thermal coal markets in Europe, South America and Asia" as a strategic consideration behind the International Coal deal.

Following the acquisition, Arch could no longer be properly characterized as a Western-focused miner, since pro forma revenue would be evenly divided between Eastern and Western operations. With sizable operations in every major U.S. coal basin, Arch becomes perhaps the closest available proxy for broad U.S. coal market exposure among the mining equities. If this deal goes through, and it has received the unanimous endorsement of both companies' boards, I may have to add a sixth selection to my list of top coal picks for the next 20 years. It is worth noting, however, that several legal challenges emerged shortly after the deal was announced, referencing allegations of a breach of fiduciary duty by the board of International Coal.

As the pool of potential targets for met coal acquisitions continues to dwindle in number, the implied scale of future deals must be seen to rise accordingly. As such, Patriot Coal (NYSE: PCX) now moves to the front of this Fool's line as a potential takeover target. To see how the next chapter in this consolidation saga plays out, be sure to add these stocks to your watchlist at The Motley Fool by clicking on the links below.