Comma use when omitting a repeated verb (ellipsis)

Question

I am 'querying' an agent... And I would like to keep grammar mistakes and infelicities down to a manageable dozen. So here goes:

In the following sentence,

   "In the story, Gilgamesh is king, and Enkidu lowly beast." 

is the second comma necessary? According to the internet, it seems so, and I tend to agree. On the other hand, I would also have been tempted to write,

   "In the story, Gilgamesh is king, and Enkidu, lowly beast." 

Is this incorrect? If not, is one form preferable over the other?

Thank you in advance.

(Note: the above sentence does not appear in the 'query' letter, but one with that structure does.)

Answer 1

As you say, this is an elliptical clause, the 'full' version being: "In the story, Gilgamesh is king, and Enkidu is a lowly beast.

For the sake of completeness, I'll give this definition from Dailywritingtips:

An elliptical construction is one in which a word or phrase implied by context is omitted from a sentence, usually because it is a repetition of a preceding word or phrase.

Your first sentence -- "In the story, Gilgamesh is king, and Enkidu lowly beast" -- is fine, and is corroborated by Dailywritingtips example of verb ellipses.

Verb ellipsis: “She favors romantic comedies, and Jane [favors] musicals.”

Your second suggestion isn't good grammatically. It looks like parenthesis, which it isn't. On the other hand it would work if, instead of the first comma, you used a semi-colon:

In the story, Gilgamesh is king; (and) Enkidu, lowly beast.

Here's an example from Grammar.com

In Illinois, there are seventeen such institutions; in Ohio, twenty-two; in Indiana, three.

However, the above example needs the semicolon to clearly keep Ohio's data away from Indiana's. In your example, it's not really necessary. My stylistic preference would be your first sentence.