The commonality between them? They all relied on the Romans being led into a position where ambushing forces could take advantage of the terrain to surround and cut off enemy forces while taking most of them out through an initial surprise attack, just like the 1st Recon did in Boulder City.

The historical Roman Legion at its peak was nigh unstoppable in a straight pitch battle (unless your name is Hannibal Barca), however, it did suffer a few catastrophic defeats like Teutoburg, Carrhae, and Trasimene.

Many folks might find it strange that the Legion is such an effective military force against the NCR given the latter's guns and modern technology, and that the 1st Battle of Hoover Dam was won by the NCR leading the Legion into what is a fairly obvious trap at Boulder City, that is if you're unaware of Roman military history at least.

The vault computer was never going to wipe out Vault 11 if they disobeyed, so nobody needed to die. The thing is, driving a race car isn't important at all, and neither is being a martyr.

In Vault 11, the vault mainframe tells you that while being a martyr isn't as fun as driving a race car, it's every bit as important.

In addition to referencing the Guy Mitchell song on the soundtrack, Cass inherited her father's heart condition.

Cass' sidequest is called 'Heartaches By The Number'.

It also doubles as a reference to Fallout: Van Buren, where would be a new type of enemy called Gehennas, mutants that are always on fire, created when the Powder Gangers blew up a radioactive coal mine in the city of Burham Springs in Utah.

Gehenna - the unique Shishkebab, is named after a valley in Jerusalem, in which - per the Hebrew Bible, some of the kings of Judah sacrificed their children by fire.

This ended with the death of 75,000 Persians. Esther, both the name of a book in the said bible and the name of the Persian queen of Jewish descent, helped prevent a Jewish genocide, by convincing the Persian king to allow the Jews to arm and defend themselves.

Esther, much like Gehenna, is named after Hebrew Bible concepts.

In biology, ester bonds connect lipids (fats).

The unique Fatman in Gun Runners Arsenal is called Esther.

New Vegas and Nevada have the same initials.

Who does Jeannie May Crawford frequently tell you to watch out for?

In 'One for My Baby', Boone trusts you to help him find and kill the person who sold his wife into slavery because you're a stranger.

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