Mooks for a Monk BBEG

[1Pirate]

My party of 6 level-9 PCs have just realized the seemingly peaceful old man in the local monastery has actually been the one manipulating the "tyrannical" King and are getting ready to throw down.

For his statblock I'm using a scaled up version of the martial arts adept(Wisdom will be at 20, Dex at 18, thinking about giving him 115 HP, +4, maybe +5 proficiency, and maybe a d10 damage die) from Volo's combined with the Diamond soul feature, Evasion, and a modest ki pool for the Mind of Mercury feature(1 ki point for an extra reaction) and Step of the Wind.(He's also getting the ribbon abilities Timeless Body, Tongue of the Sun and Moon).

Now he's also smart and wants to have minions that complement(or compensate for) his abilities, even if they aren't monks themselves.

The party's pretty optimized with a hexadin, divine soul sorc with a life cleric dip, Battle Smith artificer, moon Druid, bladesinger, and a Samurai who rolled ungodly stats so they can GMW and Sharpshooter.

Edit: Dropped in some of the upgraded stats and abilities.

[tKUUNK]

Effective allies for this old monk might include / be able to provide:

crowd control- web, hypnotic pattern, slow, or w/e

a hidden mage who casts improved invisibility on the monk

the usual counterspell helpers

and assuming this old dude has Evasion, his allies may even be willing to toss fireballs (or other dex based AoE) right into the melee, figuring this old bad dude has a good chance to entirely avoid the damage.

a minion stationed next to a lever in the temple that reverses gravity in a certain area when pulled. Most monks have slow fall....most other people do not. This could make things interesting.

[Catullus64]

Some fairly basic meat shields are a good starter; the Monk wants to be able to get into melee to inflict all of those nasty conditions he can spam, but by the looks of his stat-block he's not terribly tanky. Such meat-shields can also do some decent damage on anyone he can stun. Cultists, for instance; their Dark Devotion is like a mini Stillness of Mind!

I think that spicing up these basic minions with a touch of Monk features added to their statblock could be thematic and cool. Some of them could have Improved Unarmored movement, so they can run up walls and scurry around the rafters, hurling darts at the PCs. Some could have Evasion, so it's hard to clear them out with AoE. Some could have basic Unarmored Defense and Martial Arts, to make them slightly more threatening in melee.

If this Old Monk has been manipulating the king, a few CR 3 Knights, sent for his protection, would make thematic sense. Knights are pretty strong since they buff their allies while being fairly difficult to kill for their CR.

A CR 6 Mage could also be there for the same reason, and since you have Volo's you could use one of the cooler specialist wizards; Conjurer in particular is a very nasty enemy to face, but Enchanter and Transmuter are of similar CR.

Summary:

This is just my intuition, but about 15 CR 1/4 Cultists (They're usually CR 1/8, I'm bumping them up for spliced Monk features), 2 CR 3 Knights, a CR 6 Conjurer, and the Old Monk himself (who I would put at a CR 5, assuming you've scaled up his HP and Proficiency bonus but haven't added any features beyond the ones you mentioned) is about what would seem like a solid challenge for 6 9th-level players.

[stoutstien]

My party of 6 level-9 PCs have just realized the seemingly peaceful old man in the local monastery has actually been the one manipulating the "tyrannical" King and are getting ready to throw down.

For his statblock I'm using a scaled up version of the martial arts adept from Volo's combine with the Diamond soul feature, and a modest ki pool for the Mind of Mercury feature(1 ki point for an extra reaction) and Step of the Wind.

Now he's also smart and wants to have minions that complement(or compensate for) his abilities, even if they aren't monks themselves.

The party's pretty optimized with a hexadin, divine soul sorc with a life cleric dip, Battle Smith artificer, moon Druid, bladesinger, and a Samurai who rolled ungodly stats so they can GMW and Sharpshooter.

Roughly what does your adventuring day look like leading up to this face off? How many encouters could that potentially have before hand and how good are they are reaching to truly clever tactics?

[1Pirate]

Roughly what does your adventuring day look like leading up to this face off? How many encouters could that potentially have before hand and how good are they are reaching to truly clever tactics?

They could have one to four encounters depending on how careful they are.

They have kind of a mixed track record in terms of tactics. Sometimes they come up with interesting ideas, but have a tendency to play each encounter in a vacuum(i.e. not realizing that if they make a lot of noise fighting the monsters in room A, the monsters in room B are going to run to their aid and the necromancers in room C are going to have to time to summon their minions and cast their buff spells).

For example the bladesinger(at level 4) snuffed out all the lights in a room and single-handedly wrecked 4 human cult fanatics(as they had no darkvision).

On the other hand, several levels later, when trying to invisibly sneak into a garrison, he abandoned the lock picking plan and tried to dimension door into a Mordenkainen's Private Sanctum(which he'd learned about earlier). When that failed and two guards spotted them, he shouted for the rest of the party and cast Thunderwave on the first guards he saw. Cue the entire garrison coming after them.

[samcifer]

This reminds me of the movie The Last Dragon. It's It's worth a watch to help inspire you on running such a boss character.

[J-H]

Party of 6?
Give him Mobility (if he attacks someone, they can't OA when he moves away) and exploit his fast speed. Otherwise, he'll get locked down pretty quickly.

No Stunning Fist? It's the signature monk move.

Don't track his Ki use, just give him a "X per round" number, where he attacks 4x per round with unarmed strike (would normally cost 1 ki) and uses 1 of Stunning fist or some other ability per round.

I would also consider Legendary Actions, where maybe he can burn an extra to turn a Legendary attack into a Stunning Fist attempt.

As for mooks:
Some monk disciples are a given. Pick a school. The Mercy school from Tasha's might be an interesting choice. PCs hate it when enemies heal. Have some of them use Patient Defense as a bonus action to give attacks against them disadvantage, and they'll last longer.

-Someone who can cast Slow to further exploit the speed disparity.
-A mentalist using Mind Spike (Tasha's, 2nd level arcane spell).
-A healer of some sort, maybe a druid who casts a Concentration spell and then spends his time healing.
-A kensei archer-type (+damage, +hit) posted somewhere up high and exploiting 3D movement. If it's a 9th or 10th level monk equivalent, the archer can wall-run from one perch (with partial cover) to another whenever a PC gets close to him.

[Lord Vukodlak]

In and old campaign I gave a monk ogres as mooks. Beating the crap out of their chief with his bear hands impressed them.

[stoutstien]

They could have one to four encounters depending on how careful they are.

They have kind of a mixed track record in terms of tactics. Sometimes they come up with interesting ideas, but have a tendency to play each encounter in a vacuum(i.e. not realizing that if they make a lot of noise fighting the monsters in room A, the monsters in room B are going to run to their aid and the necromancers in room C are going to have to time to summon their minions and cast their buff spells).

For example the bladesinger(at level 4) snuffed out all the lights in a room and single-handedly wrecked 4 human cult fanatics(as they had no darkvision).

On the other hand, several levels later, when trying to invisibly sneak into a garrison, he abandoned the lock picking plan and tried to dimension door into a Mordenkainen's Private Sanctum(which he'd learned about earlier). When that failed and two guards spotted them, he shouted for the rest of the party and cast Thunderwave on the first guards he saw. Cue the entire garrison coming after them.

Ok some follow up questions. Does the BBEG know they have been found out and do they have a plan in place for dealing with it? Why were they manipulating the king and do they have any reason to be in a direct conflict?

[1Pirate]

Ok some follow up questions. Does the BBEG know they have been found out and do they have a plan in place for dealing with it? Why were they manipulating the king and do they have any reason to be in a direct conflict?

The BBEG knows he's been found out by the party, but he doesn't care at this point. He was looking for a MacGuffin(and now knows it's location) and was using the king to raid other monasteries looking for tomes about the MacGuffin. He would then offer fugitive monks "sanctuary" and get any further information of out them. He's made it appear he was heading to a remote island, but the PCs are likely to realize it's a ruse and he's heading to a mountain temple(you know how MacGuffins are). The PCs could try to catch him or try to beat him to the temple. He'd have contingencies for both. He's not really worried about reputation or anything because once he gets the MacGuffin--Wait, wait! Are you trying to get me to write your next campaign?!

[JackPhoenix]

Candlekeep Mysteries has an adventure based around master monk and his students, The Book of Inner Alchemy. You may steal some ideas from there, but it's made for level 12 characters. Still, your party is large than average and apparently well optimized, you could propably use the stat blocks as they are.

[sambojin]

4 lvl3 Druids: 1 Shepherd,1 Wildfire, 1 Stars, 1 Moon. Then you can pull out all kinds of "Way of the Bear/ Snake/ Spider/ whatever!" (Moon), "Ki blast eyebeams!" (Stars), "Kaboom teleport attack!" (Wildfire), and "Super Armour Elk Rush meteor!" (Shepherd).

And you'll have tonnes of spell slots too. Don't even write down what they have prepared, just cross off slots as you use them. Have a heap of fun with whatever looks like the most annoying thing to do with a lvl1-2 druid spell each turn, there's heaps. If they look like they're going to be in casting form a bit, maybe give them Expeditious Retreat or something to smack out of them as well.

You could even have then as recurring lieutenants, or Temple styles. Druids are easier to make as Monks, than Monks are to make as fun antagonists.

[stoutstien]

The BBEG knows he's been found out by the party, but he doesn't care at this point. He was looking for a MacGuffin(and now knows it's location) and was using the king to raid other monasteries looking for tomes about the MacGuffin. He would then offer fugitive monks "sanctuary" and get any further information of out them. He's made it appear he was heading to a remote island, but the PCs are likely to realize it's a ruse and he's heading to a mountain temple(you know how MacGuffins are). The PCs could try to catch him or try to beat him to the temple. He'd have contingencies for both. He's not really worried about reputation or anything because once he gets the MacGuffin--Wait, wait! Are you trying to get me to write your next campaign?!

Lol context is important. So the BBEG is more focused on reaching or retrieving the goal first so their choice in resources should reflect that. Delay, deny, and defend.a few refluffed iron shadows with bonus action hide/disengage would be good to use to harass and mislead the party and could use the same in the final confrontation. They would be aware of the potential of illusions and ambush so they would be hesitant to go in guns blazing if the could pot waste it on a decoy or two.

*The combination of silent image and disguise self would mean that they would have a hard time identifying the BBEG if they even catch up to their main force.*

[da newt]

Thematically I'd assume most of his mooks would be monks/ninjas too. The standard martial arts adept are pretty formidable when they spam stuns, and I'd give them all bows too. Lots of hiding, attacking from the rear, hit and run, split the party, poison, etc.

Any truly smart BBEG has a caster or 3 to help out. Pick things that work for your theme, but ensure there are some counterspell and invisibility/dimension door like capabilities.

If this guy is a true schemer / manipulator, he'll be smart enough to escape if it doesn't look like his guys are gonna win. Old guys are crafty. Is it on theme for him to jump into combat himself or is he smart enough to avoid the risk?

[Sorinth]

Anything that restricts movement can be very strong when monks are around. So some straight Martial Arts Adepts work well, or take the Shield Bash from Gladiators and add it to whatever mercenary type stat block you want.

Magic users are of course always helpful, especially if they can cast any of the wall spells. Wall of Stone in particular can be a fun option since monks can run up the wall. Though really anything that blocks line of sight to hinder the enemy spellcasters is going to be worthwhile.

That said since this is a schemer I think you'll want them to use terrain/weather to their advantage as much as possible. Especially if using hit and run tactics. Since the goal is to go up a mountain that should present numerous good ambush spots where the area is confined for anyone who can't run along the sides of a cliff. If you allow any of the Prone attacks to Shove 5ft instead it can make cliff fights quite scary even if you are nice about it and instead of sheer cliff just a very steep mountain side so that the fall is only 30-90ft. The monks can make it back up quickly, the players probably not unless they use teleportation magic.

[sambojin]

To add to the list, maybe a lvl5 Echo Knight? Just so you've got the mind/ perception/ "is this even real?"/ afterimage bit of wuxia covered. Maybe with 4 Knights on Warhorses. Let the horsey be a part of the Echo Knight's echo image. Make sure they are all dressed/armoured identically, so the party can't instantly mob the Echo Knight.

Then, a Moon druid, with a few beasts. A mixture of Constrictor Snakes and Bears makes for a fun/ easy battle. 4 of each (assume someone summoned them permanently I guess).

A Stars druid, with some Dust Mephits, some Mud(Or something else?) Mephits, and some archers. Flying can be annoying. 4 of each is easy enough.

A Wildfire Druid, with some Magma Mephits, something that casts Create Bonfire (just add it to any interesting low CR humanoid creature), and a healer of some sort. 4 mephits/bonfirers and a healer should do it. AoE and direct damage fun times :)

And a Shepherd druid, with 6 Elk, a Giant Elk, and that will probably turn into an Elk themselves at some point.

Give them all darkvision, and assume they can talk to their animals/ elementals, even when wildshaped.

That's 5 lieutenants, and you can mix/ match a bit of their mook entourage as needed, or have them team up, or have a couple of them fight alongside each other for more epic little BBEG squashing moments. And all the while the Monk is in the background, cackling away, completing his plan. Sort of twisting nobility and nature into a tool against the heroes, having convinced the circles and the orders that this is the right thing to do. Very evil, must be vanquished, before the macguffin thingo does evil monk stuff. The Druids are of a monkly temple sort, and the Knights are of the mind-bending honourable ascetic sort, so they became tools so very easily. Not evil in of themselves, so there is diplomacy and understandings allowed as a way to win, but you know, they could just be murder-hobo'd by the party too....