Looking for help creating an RPG character background

[DarkSpade]

Putting this it Off Topic since it's not a battletech character.

The game is called Wraith.  It takes place in modern times, but all the characters start the game off dead.  Each character also died with a very heavy regret.   I have a very basic outline on my character's background, but I'm having trouble narrowing down the details so I figured I'd put it out there and see if anyone else has any inspiration they could share.

- Was a solider
- Sacrifices his life to do something very heroic (not planned, split second decision).  Or at least, it would have been very heroic...
- It fails, disastrously.  Either because he made a mistake or just badluck.  (bigger the disaster, the better)
- no witnesses (at least not alive) that can confirm his good intentions. It looks like what ever went wrong was done on purpose.
- bonus points if he was able to live long enough to realize it went wrong, but not long enough to try and explain himself (like he sees the explosion in the wrong spot as all fads to black).

[Ruger]

Was going to throw himself on a grenade to protect his squad and a bus full of kids, but accidentally kicks the grenade under the bus at its fuel tank. He sees the bus blow just before he’s taken out by shrapnel from it. Maybe most of his squad too, but someone was filming the incident and it looks like he deliberately kicked the grenade over to the bus.

Ruger

[DarkSpade]

Was going to throw himself on a grenade to protect his squad and a bus full of kids, but accidentally kicks the grenade under the bus at its fuel tank. He sees the bus blow just before he’s taken out by shrapnel from it. Maybe most of his squad too, but someone was filming the incident and it looks like he deliberately kicked the grenade over to the bus.

Ruger

Still interested in other ideas since I have until Wednesday, but you've definitely inspired one!   

While working as part of a unit protecting some important people he discovers an explosive making some rapid clicking noises.  Fearing it's ready to go off without enough time to evacuate the area, he tries throwing the bomb into the back or an armored truck hoping it'll contain the blast. To the best of his knowledge, the truck wasn't supposed to be hauling artillery shells(or missiles, bombs, etc).   No one saw where he got it, but there was clear footage of him throwing something into the back of the truck before it blew.

Plausible?

[Daryk]

Another angle: he does something heroic to save someone, and before he dies (in triage), he learns that someone goes on to commit an atrocity.  Bonus points if the atrocity was in "revenge" for what happened to your soldier...

[DOC_Agren]

a concept stolen from SEALS "Fog of War"

Well on the rescue of a high value target and mr murphy coming in hard and fast on your team, your PC was pinned down by what he thought was HMG firing at him, lobs a Frag at it.  Not knowing in the area are fuel tanks, that are nothing but vapor now and more ammo.  When it goes off, lights off other things in the room, killing 2 or 3 of your own who were sepreated by the building, the HVT, HMG and another tango wearing a sucide vest.  You survived blown from building only to die on extraction.  Knowing you screwed up