What are you adding?

Nice. Let's balance this out a bit at the other end:
98 - A scroll containing a detailed plan to burn down the nearest orphanage.
99 - Pockets full of napkins inscribed with insane anti-gnome racist gibberish.
100 - A magic communication stone that, if activated, creates a magic audio connection with the lead villain of the current story arc.
- Anti-gnomery isn't bad.

5 - a cheerfully written letter addressed to the slain party's significant other, describing in glowing terms how the slain party feels like they have a new lease on life ever since kicking some unnamed and dreadful disease, and how they can't wait for this last job to end so they can come back home and start being the husband/wife/boyfriend/girlfriend/whateverfriend that they always wanted to be.
- 6 - a note with a sandwich that reads "I can't wait to spend more time with you and the grandkids, enjoy your last day!" Along with retirement papers.
  
  ROFLMAO!! It's so cringe! I absolutely love it!! =)
  
  Extra points if the slain party is a guard or other law enforcement official.

17 - little new baby shoes wrapped like a gift 🎁
- 18 - an unsend letter for the party, asking for help to recover their house as a bandit group kicked them out of it

A letter that reads:
"Dad
I know things were hard for you when mum died but I know we can get though this together.
I'll see you at the funeral.
Love from Anita"
- Last name MakeaWillSaveOrTakePsychicDamage?
  
  NP, my char has the psychopath trait.

A small puppy, obviously killed by the same blow that finished off the victim.
- "I strike at the bandit with my axe"
  "Give me a to hit roll"
  "Natural 20!"
  "You cleave both targets in half, blood sprays everywhere!"
  "Both targets?"

D100. I'm going d4 on that table.

42 - a letter describing the party’s previous actions from 20 minutes ago as a horrific crime against the innocent and vulnerable.
- Okay, this one actually slaps

If your group didn't sign up for a gritty realistic setting do not hit them by a surprise like that. Guilt and depression are not emotions you should bring to a typical high fantasy table. Not every game needs to be edgy.

"Oh wow, those scumbags really stole all that worthless, sentimental stuff before they ran into us? Serves 'em right then."

5 - As the goblin lays facedown in a pool of blood. You discover a bucket full of candy and a cracked plastic mask with the same expression of the goblin you just fought.

Holy shit thats glorious! Def gonna include that if i ever dm.

Is anyone else tired of murderhobo being ascribed to anytime a party kills anything? "How dare you murderhobo that mindflayer!" "How dare you murderhobo that zombie!"
Now, while I get the point of the post is that the bandits are still people, my comment doesn't refute that point. The point of my comment is that a DND is expected to kill in the campaign sometimes, and calling the party murderhoboes for doing so every time it happens is kinda condescending. In addition, the bandits deliberately attempted to murder the party for their money. The adventurers fought back and weren't able to pay attention to how lethal their strikes were. It adds more realism to do as the post describes, but it doesn't make the bandits better people than the party
- Back in the D&D 3.5e days, I was on a kick where I thought alignment systems were very silly so when playing D&D I'd pick an alignment and play it to a logical extreme. In one case I was playing a LN character who was a city watchman (later watch captain) who was so lawful that it became a hurdle for the party to deal with because if they committed crimes I would investigate and then arrest them. My character was also very specialized in subduing enemies without killing them, though killing in self-defense was permissible I made every effort to avoid that, not out of compassion, but because the villains should be captured and brought to justice.
  One time we were beset by bandits and some were killed in the skirmish, this wasn't a problem but the party went to loot the bodies and I stopped them. Just because you kill someone doesn't mean you get their belongings, the gold on their person would have to be catalogued and determined if it had been stolen, personal effects would go to their next of kin, etc. The party had no claim to any of it. The DM had to step in and have the King award treasure to us because I was preventing the group from getting stuff off our defeated enemies.
  Ultimately, my insistence on jurisprudence and constant arresting PCs who stepped over the line resulted in the party being forced to adopt tactics to play around me. The Sorcerer picked up subual substitution (which turned out to be broken anyway since it bypassed energy immunity) the rest of the party picked up disarming, entangling or enchanting abilities to avoid me bringing the law down on them when we got back to the city.
  All-in-all 10/10 would fuck with my party again. While sometimes frustrated by my antics the group agreed that I made the entire adventure a lot more memorable and interesting and we still talk about it years later.
  
  I get you wanted to do it for fun, but you sound like a horrible player to have at the table. There is a social contract involved in playing DnD and while disagreements between party members are all fine, your character was basically hindering the other characters at every step (at least from what you described).
  While it has nothing to do with the first point: I also reject your interpretation of alignment. It's (at least from how I see it) not that you choose an alignment and then build a character around it, but that you build a character and then classify them with the alignment that fits their actions best. I know that some classes require certain alignments but even then there are a multitude of different ways to go about that alignment.
- Partially. I think its fine to have that kind of thing. But not all the time. Bandits who are actually good people will avoid murder if possible. And while bad people can also have loved ones, that does not invalidate self defense.
  Just as you said: Self defense is not murder-hoboing. If we are talking murder-hoboing then we should apply that list to city guards and commoners, who are not meant to be fought.

100 - “ICE” patches.

I'm sorry, if the bandits didn't want to get killed, they shouldn't have jumped adventurers. I'm sorry if they had a home life, but it's not my fault my group defended itself.

Our first use of the speak with dead spell revealed that the bandit had a cousin in Neverwinter. I made it my personal quest to find her and give her news of her cousin's passing.
- "thank fuck that asshole is dead"
  
  You're not too far off. But she said it nicer.

That calls for a d20, not 100
- I think the d100 is so lots of people can add their own entries. :)
  
  I think it’s so that it’s really low odds because you have lots of fights. Wouldn’t feel real if every third encounter had something like that.

The look of fear and confusion in their eyes as the mortal wound breaks the spell controlling them

Aha! This locket is the first clue that will lead us to great treasure! Now we must hunt down this 'Fiancee'. What a weird name- must be Italian.
- The idea of this mediveal fantasy world with dragons and sorcery casually having Italians is geniuenly funny.

A letter saying you're looking for your cousin to tell them of a family endowment that was bequeathed to them, and how happy you were to meet said family member.
Describe a player in the letter, preferably one that did the murder hoboing.

My group would start collecting the shit like Pokémon cards and then want to know the value of the "art objects".

80 - a charcoal drawing on a rag of a child and adult with a heart around it
81 - a letter from a mother saying there is no crops, but they know Pelor will provide
82 - a pressed flower crown
83 - a tax notice, warning of foreclosure
84 - a letter warning a local prince wants to abduct this person, and to flee rather than give in
85 - a threat from a cult of Bahl, demanding gold or the death of their family.

How to roll 100:
take 10 sided die, roll once
take that number and multiply by 10
roll 10 sided die again
add that to the number from #2
add 1 (otherwise it would be 0-99, not 1-100)
- Alternatively:
  Roll a percentile die and a d10 together. Done.
  
  that's exactly what I said, also you'd still need to add 1 to make rolling 100 possible
- How do you get “1” like this?
  I suppose you have to roll 10 to get to 100 = 0
  But then what?
  
  Then you switch to a system where you don't add the 1, interpreting 00 as 100
  
  Modify step 2 so you subtract 1 from the roll first, then multiply by 10. That way if you roll a 1, the 10's digit becomes a 0.
- Wouldn't that give you 11-100? l The Lowest number on a dice is 1, and 1×10 gives you 10.
  The formula would have to be
  ((d10-1)×10)+d10=x≥90⟹y=(y+1)⟹z>1(d2)
  So you'd still have to flip a coin on reaching a result of 90+ in order to know if you add a +1 or not as well or else you can't get 90 as a result either.
  (This is assuming you have a d10 that's 1-10 btw and not 0-9!)
  
  there's a 0 on the die
  
  to roll 1:
  1st, 0 x 10 = 0
  2nd, 0+0 = 0
  add 1, 0 + 1 = 1
  to roll 100:
  1st, 9 x 10 = 90
  2nd, 90 + 9 = 99
  add 1, 99 + 1 = 100