After spending some time in the dungeon (6 months? 20-40 sessions?), my players started recruiting some guys to come with them. Partly because not every player could make every session, so they'd have the option to pad out the team, and partly because the threats in the dungeon were very scary, so they could bring back up if they hit a hard spot. But we all like video games and leveling up, so I gave their followers levels and an upgrade tree.
XP is split evenly with followers when brought along. You can only bring a number of followers to equal the total number of players + 1. Since our group usually has 4 players, the largest a group can ever be is 5. Meaning if two players join a session, they can bring all three NPCs, and if all four players are present, they can bring one.
If a session has players joining or leaving early, it's okay to teleport followers in and out. It seems worth it to handwave the details in this case.
Followers are controlled directly by players during combat, but won't do anything against their nature. PCs will have to negotiate with or convince followers as normal to do strange or untoward actions, and conversations will be roleplayed. If a follower dies, they can be brought back from the dead, but depending on the circumstances and the players' actions, might not want to fight anymore. This happened to Zaxas, it sort of sucked and I miss him.
Follower stats are determined when they're hired, and depend on their innate capabilities and characteristics. If the players decide to hire some dumb schmuck, they'll have stats to reflect that.
My players were level 15-17 when we started this and their hirelings are statted to reflect that. They hit level 2 and level 3 with about one session of play each, and then levels 4 and 5 a little bit slower than that.
Are the NPC powers overpowered? Hell yes they are. But the NPCs are pretty flimsy so I think it balances out.
HIRELING XP CHART
LEVEL 2: 1,000
LEVEL 3: 3,000
LEVEL 4: 6,000
LEVEL 5: 10,000
OCEAN BRACK
A rich adventuress from the Moriad. She travels with a ton of money and a craving for new adventures. The players met her when she was bidding for a magic diving bell which can transport the occupant to hell. She went to hell once and came back safely, and they convinced her to travel with them to the Shattered Labyrinths of Illith Varn to seek new knowledge and experiences. Her gimmick is she can gift the players gold instead of upgrading her stats. If they choose this, the gold does not apply to XP.
Ocean Brack
HP 11, AC 11
Attack +3 1d8+1 (Rapier)
LEVEL 2: +2d8+2 HP AND +2000 GOLD or +2 AC
Choose one:
HELPFUL KNOWLEDGE (May make a knowledge check with a +10 bonus on pretty much anything, if successful cannot be used until next day)
DODGE (Reduce damage from incoming attack or spell to 0, useable once per day as reaction)
PERCEIVE WEAKNESS (Spend entire action studying foe, then at start of next turn may impart knowledge to give allies within shouting distance +5 on next attack, useable once per day)
LEVEL 3 +2d8+2 HP AND +2000 GOLD or +2 Attack
Choose one:
PARRY AND RIPOSTE (1/turn If hit with an attack, may parry as a reaction to provide her a +d10 AC, if attack then misses, she may riposte)
DISTRACT (Hurls insults at opponent, which must make Wisdom save, on failure is at disadvantage to attack anyone but her, used once per short rest, lasts one round)
LET ME TAKE A LOOK (Makes a Perception or Investigate check with a +15 bonus, useable once per short rest)
LEVEL 4 +2d8+2 HP AND +2000 GOLD or +2 to two saves AND sneak attack 2d6
Choose one:
MAKE A NOTE (Makes notes in her journal exactly describing events as she sees it for up to one minute, including room layout, monster behavior, things spoken, etc, useable once/day)
SNEAK ATTACK (May now sneak attack once per turn with a +4d6 dmg)
MY FATHER KNEW A FELLOW LIKE THIS (Make an opposed Charisma check with a +15 bonus, on a success target treats Ocean as a friendly acquaintance, just like Charm person)
LEVEL 5 +2d8+2 HP AND +2 to two of your choice: AC, ATTACK, or TWO SAVES
Choose one:
I SUPPOSE THIS ADVENTURE IS REALLY WORTH IT (+10000 GOLD)
HELL MOVE (Attacks five times with a +4 bonus to attack, and may sneak attack with each attack, if the target is killed, a demon is summoned from the corpse of the slain which serves Ocean Brack for one day and one night; the summoned demon is chosen randomly from a secret DM list, or generated randomly; my secret demon list is a spread of standard monster manual demons with a roll of 20 summoning a balor, naturally the first time they used this power they summoned a balor and used it to steamroll a good chunk of the dungeon, I'm still mad about it but fair's fair)
CRODA THE WOLF
Croda is a giant speaking wolf who fights with a sword in her mouth. I honestly don't remember her backstory at all, except that she hails from frozen Velenheim, kingdom of the white elves and their dead armies. I imagine the wolves there might train in weapons to better hunt their prey. Maybe her pack was killed by elves or zombies.
Croda the Wolf
HP 31 AC 15
Sword attack +5 1d10+2
Bite +5 1d8+1 and trip
LEVEL 2: +2d12+8 HP, +2 to AC or ATTACK,
and CHOOSE ONE
SPIN ATTACK: attack all adjacent, anyone hit is knocked down (1/short rest);
SAVAGE LEAP: After making a successful bite attack, leap up to half movement speed as disengage and then bite again, but must make a bite attack.
KICK: May kick as a bonus action each round for 1d8 dmg and knock back 5’
LEVEL 3: +2d12+8 HP, +2 to TWO SAVES or DAMAGE,
and CHOOSE ONE
ALL ONCE PER DAY:
STRANGE HOWL (All enemies within 60’ must make Wis save or spend next turn using movement crawling like maggots, means movement halved at very least),
MOON HOWL (Sheds sickly moonlight from no-where, enemies within 60’ take 2d10 radiant damage, no save),
FOND HOWL (Allies within 15’ gain 2d10 temporary hit-points that last until sunset or sunrise, whichever comes sooner)
LEVEL 4 +2d12+8 HP, +2 to AC or ATTACK,
and CHOOSE ONE
ALL ONCE PER SHORT REST:
QUADRUPLE SLASH (Attack four times with wielded weapon, recharge on short rest),
BITE THE BLOOD (1/short rest, On a successful bite attack, heal 3x that amount on self),
CRODA’S DANCE (1/short rest, Use all movement speed to perform a strange dance, next attack roll gains a +10 to attack roll and if it hits, target must spend their movement on next turn dancing, and then attack Croda back at least once)
LEVEL 5 +2d12+8 HP +2 to TWO SAVES or DAMAGE,
and CHOOSE ONE
MOONLIGHT GREATSWORD (1/long rest wielded weapon now deals +4d6 radiant damage, sheds silvery green light in a 60’ radius, and may shoot beams of moonlight up to a range of 30, dealing damage as the sword; this lasts 1 minute, after which the weapon degrades into rust);
MASSIVE FORM (1/long rest grow to size huge, gain +40 hitpoints, +4 to damage, advantage to strength checks and strength saving throws, and +20 to move, this lasts 10 minutes)
ZAXAS THE MANTIS-MAN
A mantis-man from the Black Jungles of Abazidun, who has ventured north into the wastes of ruined Orostranthy to discover the world! Friendly, wide-eyed, pure of heart, somewhat timid. He looks like Zorak except with mantis blades instead of yellow gloves.
ZAXAS
HP 28 AC 18
2 attacks with mantis blades +6 1d8+2
Movement 40, and may jump up to 40 feet
Acrobatics +8
LEVEL 2: +2d8+6 HP, AND +2 DAMAGE or +2 AC
Choose one:
TWIRL (After hitting an opponent, may use a bonus action to attack another different adjacent opponent),
DECAPITATE (Now deals a critical hit on a 17-19, while a natural 20 deals triple damage),
FINE SONG (Sings a fine song in battle, giving allies who hear a +1d4 to attack, saves, or damage, this roll is useable once every ten minutes but only during battle)
LEVEL 3: +2d8+6 HP AND EXTRA ATTACK AND ACROBATICS +5
Choose one:
HYPNO-EYES (Make eye contact with an opponent as an action, opponent makes Wisdom save, on failure is charmed, incapacitated, and has a speed of 0, as long as Zaxas maintains eye-contact, if it takes damage or is shaken awake, useable once/day),
CAMOUFLAGE (Zaxas may blend in with his surroundings, giving him a +15 bonus to stealth, and 1/day forcing opponents to attack him with disadvantage for 1 minute),
EXCELLENT BLOW (A single attack this turn that hits deals +2d8 damage and causes opponent to drop whatever they’re holding and may not move on next turn and attack with disadvantage for next turn, useable once per day)
LEVEL 4: +2d8+6 HP AND +2 ATTACK or +2 AC
Choose one:
RAIN OF BLOOD (For 1d4 turns, each attack targets opponent and adjacent target, 1/long rest),
I DINE ON YOU (Zaxas gains an additional bite attack for +1d6 dmg),
HAVE AT THEE (Every time Zaxas attacks, he may move forward 5 feet and force the target to move backward 5 feet, if this would put the target into a hazard, there is an opposed Strength check, if opponent wins Zaxas cant move them anymore this round)
LEVEL 5: +2d8+6 HP AND EXTRA ATTACK AND ACROBATICS +5, AND CHOOSE ONE: +2 AC, +2 ATTACK, or +2 to TWO SAVES
Choose one:
RADIANT SCREAM (Zaxas screams, the built up radiation of the Black Jungles locked in his body are projected from his spread wings. This creatures a blinding light. All creatures in a 60’ Cone must make a Constitution save DC 16 or take 6d10 Radiation damage; Success means the target takes half damage; on failure, they are blinded and suffer 2d10 Necrotic damage at the start of each turn for a minute as their body decomposes, they may save again after taking damage to end the effect),
I AM YOUR DEATH (Zaxas attacks six times, and may jump to disengage up to half his movement speed between each attack. The first attack targets all enemies adjacent to Zaxas. The second attack inflicts a bleeding effect that repeats the damage incurred for 1d4 rounds. The third attack targets all enemies in a 15’ cube adjacent to Zaxas. The fourth attack is a sneak attack that automatically deals +4d6 damage. The fifth attack knocks back the target up to 15’, granting a Strength save DC 15 if it would place them in a hazard. The sixth attack is treated as a roll of a raw 20 and deals triple damage.)