If two Libras are on your force and they're the only friendly figures left, would both Libras be able to modify their attack values by +1? I see nothing in the wording of the SP that would prevent this but I'd prefer to ask than just assume.

Here's the text of the SP:

Heh, that's a wacky one. I would love to run a Libra team now just to exploit this silly wording.

I'm gonna say no, there's no way GD would have intended this.

But the way it's worded, if you had a team of nothing but Libras, they would all have a +1 attack.

Yes, they can.

Is "highest" inclusive? Does (s)he get the bonus if there is another figure with the same point value was on the map?

That ruling seems odd

If Libra is the highest point friendly character on the map, modify his attack value by +1

Because, when you are down to two Libras, they are tied and thus are not the highest

Take Richard Fisk (please!)
Supreme HYDRA, For Now: Once during your turn as a free action, choose the highest point friendly character with the HYDRA keyword. The chosen character can use Mastermind until your next turn, but only to deal damage to characters with the HYDRA keyword or team ability.

So if two characters of the same point value that qualify are in play will both gain Mastermind?

Ditto Maria Hill for SHIELD and Enhancement

Here is the final word on Fisk

Well, Libra's power is an If/Then sort of situation. Richard Fisk requires that you choose the character with the highest point total. Tied for points? Choose one, similar to the Superman Enemy TA.

No, as the final word says only one will get the Mastermind from Fisk, but if you had two Fisks on your team, each Fisk could give Mastermind to a different "highest" cost character because both tied high-cost characters are highest cost characters. (Presuming Fisk isn't unique, I haven't checked.) Fisk's limiting factor is "choose the", not "highest point friendly character".

SE TA last line: If the two characters have the same point value, their controller chooses which is treated as the higher point character this turn.

I do not see this in Libra's power. All I see is 'if he is the highest point character'. And, based on the precedent of 2000AD (I choose a Libra, it means THAT Libra), there is no option for a tie. Each character is unique unto itself, he either is or is not the highest point character

What if the example is Libra and Avengers' Black Panther. Both are 92, when you ask the question 'is Libra the highest, the answer is no, he is tied'

The choice in Fisk and Hill's is a requirement that the bonus does not automatically pop up when the conditions are met. Libra's pops up automatically if he does. If you forget to take the free action to give someone Mastermind on your turn, you don't get to use it on mine

If you have two characters that are the same point value, and no character has a higher point value than them, they are both the highest point character.

Wow, this is confusing why can' they be the lowest point charaters
So if 2 Libra's are on the map they qualify for the +1 since they are both the highest point characters. And if one Libra and Black Panther are on the map with the same point value they are both the highest point characters but Libra does not qualify for the +1 because of the If Libra is the highest point friendly character on the map,but there are 2 friendlies with the highest point, Libra is not the only one.Just trying to get clarity