In modern day combat, what would warrant singing during battle?
<PERSON> the singer is having a downtime in his career.
Over the millennia, <PERSON> sang anywhere from royal courts to farmers' cottages and have been rewarded with many, many hand-claps. But to keep going, indeed to preserve his immortality, he must sing - in battle.
When leading a charge to meet the enemy, <PERSON> would raise his mighty voice and sword in song, inspire his troops - and his superpower. Yes, the secret behind his long life is twofold:
The first: Singing in battle makes him as strong as three men, and impervious to attack. Even a ballista bolt couldn't scratch him, so long as he's singing with at least two of his men within earshot, fighting against at least two of his enemies.
The second: Singing in battle at least once every couple of years keeps him from aging, thereby letting him live for millennia.
* At least four men must be fighting, not including himself.
* The intent to kill the other guys is what constitutes a fight, so they can use long range weapons, even cannons or missiles. However, the field must be such that his guys will have at least caught a glimpse of some of the enemy, at a point in time that's close to the time of the attack (firing a missile at people so far away that you can't ever see them doesn't answer the requirement of "a fight").
* For the same reason, the fight can't be a mock fight (e.g. practice or a fun bar fight). An intent to kill is required.
* Earshot means that at least two of his troops must be able to hear his song.
* <PERSON> doesn't particularly like to fight, but he's good at it and the troops love him for both the songs and, well, the fact that his side tends to win. 950
So every two years, at least one fight.
This was all well and good in the old days, when a good charge with melee weapons constituted a good fight.
Nowadays, however... There are plenty of fights to be had but not the kind where singing is appreciated. Indeed, as recently as the 19th century <PERSON> has faced frowns when singing while the battle rages.
In this day and age, where concentration and stealth is a prime concern in battle, he was threatened with removal from duty for singing at the wrong times. This almost made him come forth and tell of his abilities, but he absolutely does not want to be probed and bisected by scientists who'll want to check what makes his superpower tick.
So the question is: What kind of situations in modern day combat warrant loud singing by at least one particular combatant? The bigger the advantage one side gets by the singing, the better the answer.
* For the sake of the question, lets assume that other noises (e.g gun/cannon fire, screams of the dying) are not getting in the way of <PERSON>'s singing.
Edit 1: I really should have clarified this - I want <PERSON> to be running in the field and getting smacked with fire and brimstone (bullets and heavy ordinance) from time to time. So, infantry. He can be in a tank for a bit of the fight but the point of his imperiousness to harm is to get an unhinged singer into the thick of it. I'll worry about people not noticing his invincibility later...
Edit 2: For those still complaining about other noises, as I wrote - hand (ear?) wave it. Part of the superpower is that the singing subdues noises that are undesired by the audience (which can be a cool advantage by itself, just not so relevant to this question). 950