Be me, DM, DnD veteran of 7 years. Be not me, cleric, paladin, bard, druid, and fighter, all new to DnD Running them through Lost Mines of Phandelver as it's a good first timers module get to part where you get a job to kill orcs describe that have been raiding homesteads paladin player starts dropping hints, talking about wiping them out fighter is half-orc, dropping hints about peaceful resolution message paladin, reminding him that oath of ancients holds mercy as a core tenet, an she could break his oath, says he understands party gets to orcs, have fighter distract while rest of party gets closer fighter starts honor duel with orc leader, party can't tell it's a duel because no one speaks orc jump leader, killing him, and the other orcs try to flea paladin screams "no prisoners, no mercy!" And beheads a fleeing orc. fighter player is upset, and the paladin player literally says something like "it's what my character would do because my tragic backstory" fighter player asks if PvP is allowed, decide fuck it, let's see where this goes (these two were also a recently seperated couple the fighter had already told me that they were in a bad mood today privately) fighter decides to roll to see if they attack paladin, but dice say that they shouldn't fight right now rest of party goes full no mercy and wipe orcs to the last, even chasing them through the forest. fighter tries to stop them, bars catssleep on them and tries her up, fighter rolls high athletics to break out and run repeat previous step two more times fighter and paladin duel, get split up by rest of party cleric, who shares body with a fiend, has fiend take over body and has them side with paladin Brad is trying to stay neutral but agrees with paladin druid abstains an hour of pvp and in-character bickering ensues as I hope they sort it out I stop them for a bit to make sure no one is having a bad time they all speak up at nearly the same time and say...this is the most fun they've ever had! they all laugh briefly and then get back into character and keep playing this out paladin realizes that he lost his paladin powers, decides to double down and become an oathbreaker to "punish those that harm innocent people, no matter what" fighter is pissed, but they decide that the gold is worth too much to leave after session I talk to them and they all repeat it was an amazing session, and fighter messages me thanking me for letting them all go wild with it and saying it made their whole weak and that they were in a much better mood. and I got to watch the shit show and laugh my ass off the whole time and had a great time

Sometimes letting people go at it and really get into character gives you some of the best character drama moments you've ever seen. Eat your heart out Hollywood.