There's not a lot of cohesive themes for a spellcaster that the game supports with out-of-the-box spells that just fit, like you definitely can be the fire guy and you can be the illusions guy sort of, and you can flavor the spells to fit your concept, but if you want to be the lightning guy the spells are a bit shit, generally you end up with a guy who can do all sorts of things, that don’t all match each other.
But one guy the game has always supported is the hand guy, and thats … fucking… dumb… but you can do it. And its clearly because one of the guys in Gygax’s campaign thought it was a fun concept and it just sort of got grandfathered in. But who is this guy Bigby, and what’s his deal? Well whenever I read into the histories of all the dudes in Greyhawk it’s revealed that none of that stuff is all that interesting or relevant to my game, and the guy I was imagining was better anyway, so let’s try to reverse engineer a guy who fills the gloves, instead.
So my ultimate goal here is to flesh out all the material you would need if you wanted to play Bigby in 5e from first level to whatever level he needs to be to be THE TRUE BIGBY of legend. I’ll crush him down into some statblocks that are 5e monsters, so he can be a villain in a campaign. And hopefully along the way I’ll give you enough juice to want to field this guy. What is the deal with the hand guy?
My intuition is to make a caster who’s not terribly good at magic, and whose interest in magic is basically as a means to an end - and that end is making extra hands to do extra things with. The hand is a perfect implement for most any task he is willing to imagine. So we do not really need spellcasting beyond this, and we would not wish for it. This suggests a Arcane Trickster rogue -this would grant us Mage Hand Legerdemain at third level, which is a clearly better version of Mage Hand, which was always going to be our first choice of spells. I dont think any self-serious Bigby would be without the Mage Hand Legerdemain, because the idea that some other caster is using Mage Hand in ways that he cannot would frustrate this Bigby. But he can’t go all the way to 20th level with Arcane Trickster Rogue, because the spell, Bigby’s Hand, is a 5th level spell, and the arcane trickster is a half caster so it never gets to 5th level spells. But we can know that it’s three levels of Arcane Trickster at least, so why not start with that.
So our Bigby starts out as a petty criminal, makes a name for himself as an ambidextrous pickpocket and picklock, kind of a scrawny guy, sticks to the back, good if you need someone to open a safe, cheats at cards. People start calling him “The Hand”, becomes sort of infamous. He’s a manipulator, rises through the ranks as a smuggler, he’s a regular. Relies on underlings too much, ultimately is betrayed too many times, decides to become more self-sufficient, turns to magic. So the monster version of that guy looks like:
Bigby, Cunning Manipulator
Medium Humanoid, Unaligned
Armor Class 15 (chain)
Hit Points 35 (5d8 + 10)
Speed 30 ft.STR DEX CON INT WIS CHA
10 20 (+5) 14 (+2) 16(+3) 13 (+1) 14 (+2)
Skills Perception (+3), Stealth (+6)
Expertise Sleight of Hand (+10), Persuasion (+6)
Condition Immunity charmed
Senses Passive Perception 13
Languages Common, Thieves' Cant
Challenge 2 (450 XP)
Improved Mage Hand Legerdemain. When he casts Mage Hand, Bigby can make his spectral hand invisible, and can use it to stow or retrieve an object the hand is holding in a container worn or carried by another creature, and can use it with thieves' tools to pick locks and disarm traps at range.
Bigby can perform these tasks without being noticed, if he succeeds on a Sleight of Hand check vs that creature's Perception.
Bigby's Mage Hand can be used to make attacks (hand crossbow/dagger) on targets Bigby can see, or to deliver touch spells.
Multiattack. Bigby makes two attacks with daggers and/or hand crossbows.
Dagger. Melee or Ranged Weapon Attack: +7 to hit. reach 20/60 feet, one target. Hit: 7 (1d4+5) damage.
Hand Crossbow. Ranged Weapon Attack: +7 to hit, reach 30/120 ft, one target. Hit: 8 (1d6+5) damage.
Cunning Distraction. Bigby can use a bonus action to Dash, Disengage, Help, Hide, interact with an object, use Mage Hand Legerdemain, or make a weapon attack. If he has a Mage Hand active or casts a spell on his turn, he can Hide even if only lightly obscured, and gains advantage on any check (not attack) made as part of this bonus action.
Uncanny Dodge. When an attacker Bigby can see hits him with an attack, he can use his reaction to halve the attack's damage against him.
So I think that works fine for a low-level Bigby. I'd put him in a group of regular thugs and not mark him as special until he starts doing weird stuff. Have him try to steal something from the party and escape unnoticed. A reasonably well-equipped party will still obliterate him but this is the plight of all creatures with hit points. I think he can maybe stick it out a couple rounds, if he has help, and I think he sort of has a reasonable chance of escaping to become a recurring villain or someday invent the spell Bigby's Hand, which is probably the goal here.
To even cast that spell, he can't be a straight Arcane Trickster, and needs to stick nine levels in Wizard, or Sorcerer, or Artificer. This puts us well beyond any spellcaster I’ve personally ever played, but Bigby, at this point in his career, I suppose, is determined to unlock the fifth level of hand magic. To do less would be insufficient. So this later Bigby is at least a 12th level character, and a spell researcher, and a single-minded one, at that. So this is, I guess part 1 of a longer Bigby mythos, so expect more parts to follow.