A vegetarian akin to the triceratops fought a meat-eater in the tyrannosaur mold millions of years ago in Montana (see pictures at bottom). They both lost, but the remains of their battle are forever preserved in history. At least that's what paleontologists deduced when they found the fossil of the interlocked dinosaurs.

The two-in-one fossil will go on sale at the Bonhams auction house next week in New York, Reuters reported. In combination with another 80 fossils on auction, the "Montana Dueling Dinosaurs" fossil is part of a "lifetime opportunity for institutions and collectors" and "the most important dinosaur fossil sale of all time," said Thomas E Lindgren, Bonhams Co-Consulting Director of Natural History.

One of the most exciting parts of the entangled dinosaurs - one officially a ceratopsia; the other most likely a nanotyrannus -- is the discoveries that still remain hidden in their bones. Because they haven't been thoroughly studied yet nor have they been mounted, their future owner could discover important information about the Cretaceous period of which these two dinosaurs were a part, Bonhams reported. Scientists haven't even officially identified the T-Rex-like fossil, according to Reuters. Though Bonhams calls it a nanotyrannus on its website, some scientists believe it could be a new species, Reuters reported. The fossil, discovered on a range in Montana, is also incredibly complete, which should help lead to a more certain identification once the specimen undergoes further examination.

Given their scientific potential and unique position of death, the Dueling Dinosaurs could break the record for highest price ever paid for a dinosaur fossil, previously held by a T-Rex skeleton that went for $8.3 million in 1997, according to Reuters. Bonhams estimates the final price to range between $7 million and $9 million. In total, Bonhams expects around $15 million to be spent on fossils. The second biggest prize is a 38-foot Tyrannosaurus Rex skeleton, projected to command between $1.8 million and $2.2 million.

The fossil hunter who found the two dinosaurs in 2006 hopes a philanthropist buys it and donates it to a museum, according to The Associated Press. A museum could also purchase it directly, Reuters reported. The last major dinosaur sale at Bonhams created some controversy when a Tyrannosaurs bataar fossil found in Mongolia sold for $1 million dollars, but was eventually sent back to its place of origin after officials deemed it illegally poached, according to Reuters.

No clean getaways for either the nanotyrannus (below) or the cetatopsia (further below). (note: cetatopsian picture, courtesy of the Smithsonian, is of a xenoceratops, a member of the ceratopsian family that resembled the dinosaur in the fossil.)