Cowardice, Treachery, Ineptitude, Insanity

You're a busy GM. You don't have the spare time or brainpower to give every hireling a different personality. What you can do is give them a unique way to flip out under stress.

Roll up one of these for as many hirelings as you can keep remembering this stuff for. Whenever an appropriate situation comes along, roll a morale check. If they fail, they do whatever treacherous, cowardly or inept thing you've rolled for them.

1. Cowardice

1. Uncontrollable shakes: -4 to all rolls.
2. Paralyzed with fear.
3. Flees.
4. Blind panic: attacks everything at random, friend or foe
5. Won't stop screaming: roll for wandering monsters.
6. Falls prone and drops whatever they're holding.
7. Deserts if the party sleeps in the dungeon
8. Tries to surrender
9. Cracks under the pressure of slow exploration and runs wildly through the dungeon.
10. Holes up in a room and refuses to keep going

You can roll d6 on this table to get a Panic result any time the henchmen see something that would send them screaming.

2. Treachery

1. Steals from party. If they think they're about to be discovered, they frame another henchman.
2. Sells out the party to a dungeon faction for thirty silver pieces.
3. Convinces other henchmen to mutiny and stab the party in the back when they find a good haul.
4. Cheats other hirelings at cards when the party rests: fights break out.
5. Thinks they know better than the party. Contests their decisions, rousing dissent.
6. Bargains for better pay at the worst possible time.
7. Snitches on the party if they do anything illegal
8. Leaves in the night, stealing as much treasure as they can.
9. Paranoid: Believes the party has betrayed them.
10. Cuts and runs when the party needs them to get out of a jam.

3. Ineptitude

1. An important piece of equipment breaks mid-use due to their shoddy maintenance.
2. Loses the things entrusted to them.
3. Shaky hands: Drops what they're holding at a crucial moment.
4. Bad cold: Sneezes when the party's trying to sneak.
5. Cries all night. Can't sleep.
6. Snores all night. The rest of the party can't sleep.
7. Stress eater: Eats all of the party's rations at night.
8. Has a terrible disease. Failed morale check means they won't reveal it, and the party will catch it if they rest together. (If you can't think of anything better, -2 max HP every day until they reach 1 HP).
9. Highly superstitious: Abandons party if they see them perform magic.
10. Conceals open wound - they didn't want to seem weak. Attracts wandering monsters.
11. Too old for this shit: needs to rest every hour.

4. Insanity

1. Old soldier: has vivid flashbacks, believes they're in the middle of an old battle.
2. Bitter hatred for another hireling: tries to slit their throat at night
3. Madly in love with another hireling: They sneak off for the sick thrill of dungeon sex.
4. Addicted to purple lotus. Horrible withdrawal: hallucinates monsters, +5 to critical fail chance.
5. Refuses to back down from a fight, no matter how hopeless.
6. Suicidal.
7. Beserker rage: Attacks the nearest thing, friend or foe, until they or everyone else are dead.
8. Fatalistically accepts death.
9. Leave no man behind: Refuses to abandon a single fellow henchman
10. Finishes off fallen PC's - "There was no hope for them, I just eased their pain."

Roll a d4 and a d10 to get the list and entry for your terrible hireling. It'd be better if they fit into a single list that you could roll one dice on, of course - anybody out there want to finish this off?

I've been on this hireling tangent because I'm planning to try all the bits of old-school dungeon crawling that I've previously ignored. Starting with DCC has crippled some aspects of my D&D education: I never understood hirelings, charisma, wandering monsters, light sources, player mapping. The slow and dangerous exploration of a megadungeon has been totally absent from my campaign. Maybe I'm not even old school.

Tavern Roll

Before you enter the dungeon, you can make a Tavern Roll to pick up information or hire people. Roll d10+CHA, and look up the result on the table below.

0 or less: You've tipped off one group of the dungeon's inhabitants. They'll be prepared for you.
1: Your loose lips have inspired a rival group to try and beat you to the treasure.
Roll 2d6, and subtract one from the other. If it's a positive number, they'll arrive at the dungeon that many hours after you. If it's negative, they'll arrive that many hours before you. You can get a bonus or penalty to this roll if you take a faster or slower route to the dungeon.
2 or 3: Inept, cowardly, or treacherous Hirelings.
4 or 5: False rumor
6 or 7: True rumor
8 or 9: Loyal and/or skilled Hirelings.
10: Roughly sketched map of a small part of the dungeon.
11+: You've got an inside man. Choose one of the groups that live in the dungeon. One member of that group will help you, for a price. Leaving doors open and such will be cheap, helping to kill their comrades will be very expensive.

Warn your players: Rolling here means they'll be spreading information about their quest, and if they roll badly they'll attract unwanted attention. Make the roll in secret, so they don't know if their rumors or hirelings are trustworthy.

The d10 means Charisma has a serious impact, but every player can get a good or bad result. With +3 charisma, for instance, you still have a 20% chance of  getting a false rumor. Nevertheless, the players will trust information and hirelings gathered by a player with good charisma, and distrust anything found by a player with bad charisma.

Each roll is one night in a tavern, buying drinks and chasing up leads. They can roll as many times as they want, but the good information will slowly go dry and observers will start to get suspicious. Give them -1 to the second roll, then -2, etc.

Edit: If someone is only interested in hiring retainers, not gathering rumors (or vice versa) just change the Rumor entries to Hirelings (or vise versa). If searching for rumors, 2-5 would become false rumors, 6-9 would become true rumors.