D&D 5E Suggestions on how to handle NPC on Monster/NPC combat?

[jgsugden]

If I know that the fight is coming, I'll roll it up in advance (quickly) and then walk through it in real time speed (6 seconds per round) until the PCs (almost inevitably) interfere. I find this is a good way to remind the PCs about how fast combats actually are. It may take us an hour to play it out, but the combat is actually less than a minute long.

At times, I do not roll it out, but instead just roll percentile dice and use that to decide how the combat will play out, then I just tell a good story of the combat. Example: NPC Bob the Knight is going to face off against an Ogre. The Ogre hits harder, hits more often, and has more hps. I decide it will win 80% of the time. I roll percentile dice. A very low result will be a fast victory by the ogre. A 50 would still be a victory for the ogre, but it would take longer. An 80 would bring both combatants down. A 90 would be a surprise win for Bob. A 100 Would be Bob surprisingly one shotting the ogre. It reduces a lot of playing with myself to one toss and then a good story. Yeah, I know what I said.

If I didn't expect the fight, and it is meaningful, I have the players take over the roles (and rolls) in the fight, if I trust them to role play it out in character and do their best.

 

[Eyes of Nine]

Example: NPC Bob the Knight is going to face off against an Ogre.

If he throws a chair at him, instant critical hit with max double damage.
(only funny (and only then, barely) to those who followed US college basketball prior to 2008)

 

[Eyes of Nine]

Thanks all for the tips, lots of great ones here.
I usually do the "let the players roll" thing; and even will let them control the NPC's behavior within reason.
But I'll suggest them to this new DM so he doesn't get too into monsterbating...