Question

I don't know 5E, but I assume they have a list of NPCs based on some kind of CR. So just pick an appropriate amount of NPCs with an appropriate CR.

Or you could get creative, use ranged attacks with environment advantages and well placed traps.

We can't help you if we don't know about your setting.
Give them class levels?

Try making the humans higher level, higher numbers, organized, and not act like suicidal retards.

Intelligently played humans should give the players a serious run for their money.

have them better equipped, better trained, more skilled, more numerous, give them some heavy support, place them in position that gives them advantage, create situation where they get the drop on your players, use enviroment to make fights harder, give the opposition some interesting abilities that would force players to think around them...

Who cares? "Make fight challenging" is not some precise science, but rather question of GMs skill.

okay, then what the fuck is it if not fantasy genre?

alright, breaking down a thought.

You use the NPC stat blocks in the back of the monster manual and volos guide rather than monster stat blocks, and give people unique and reasonable features or abilities from other blocks.

Realize that different groups of people would fight differently and employ different tactics based on what information they have about the party.

Things like pack tactics, or various martial advantage abilities you see in more combat minded monster stat blocks.

In the future, please read the fucking book and when you write an opening post to a thread with a question do us and yourself all a favor and include all relevant variables and try to find a relatable picture because that image hurts. It fucking hurts and i hate you. It is like starring into madness.

HOW WERE WE SUPPOSED TO KNOW THAT IF YOU AREN'T TELLING US WHAT'S IN YOUR SETTING YOU FILTHY PIECE OF DISTENDED ANAL SPETUM.

Easy. Give the enemies A BUFF TO STATS and BETTER EQUIPMENT.
How about you pick up that neat little book you got there called The Dungeon Masters Guide,
and then proceed to read it you shut-in NEET

Increase their stats you spastic.

neets are god tier

>posting a forbidden image

t. neet

God, that pic makes my skin crawl

What a shitty bait thread

Hyuck

not bait

Go fuck yourself.

And to everyone else in thread, stop trying to help such a retard.

It helps if the PCs aren't human. That way the humans can use their Cantus to full effect without dying the Death of Shame.

At least I asssume your setting is Shinsekai Yori since you haven't told us otherwise.

Have a friendly GSV upgrade the NPCs with e-dust and drone-equiv brains. They can think and fight at a microsecond pace, plus they'll be much more adaptable to their environment.

At least I assume your setting is The Culture since you haven't told us otherwise.

It's goofy time

No Dad No!

A huge proportion of fights in earth’s have been against humans.

Humans can be pretty hard to fight you know

Don't let players play with all their toys. How? Stop them, with grabs. Grappling is scary because if you're grabbed you can't do things.
Dungeon Grappling. (Book's compatible with OSR games, 5e, and 3.PF). It provides native-level grappling rules for D&D. While I haven't used this, I have used this author's GURPS grappling rules and they're pretty sweet. heaps of examples on his blog too. gamingballistic.com/category/features-on-gb/grappling-mat/

No one here cares about your shitty Super Speshul Secret Setting, you aspergic fuck. Give us details so we can adapt a system, or go make friends with a rope.

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