The story we will always talk about is when I had a group in front of a building and I put their miniatures there and two Gargoyle miniatures next to the stairs heading up to the entrance. I never intended the gargoyle's to come to life and attack, but the players were determined that they will do exactly that and literally spent an hour trying to figure out a way to get them to spring to life. Attacking them, trying to talk to them, enticing them to attack, looking for a trap trigger, it was hysterical watching them mess with these two statues. I didn't even bother having the front door locked cause they spent so much time on that.  

Playing LMoP. Myself (DM) and my party are entirely new to the game so (at the time) we didn’t know what we were really doing.

The party is inside the Redbrand hideout. They find a door and attempt to crack it open to see what’s inside. They elect the rock gnome to try his best. The gnome rolls a nat1. The door falls off it’s hinges, alerting the Ruffians inside. We roll initiative. The first Ruffian charges the door and swings at the gnome. Another nat1. He thought the gnome would be a lot taller and ended up swinging too high and hitting the door. The gnome goes next, disengages, and runs down the hallway, leaving the rest of the party to fight 6 Ruffians without him.

Later in the fight, the half-elf successfully Intimidates a Ruffian, causing him to run away. The half-elf chases him, only to follow the Ruffian into a room containing three Bugbears. He froze for a moment. Then left and closed the door behind him. Another party member asked what was in there. The half-elf says “Broom closet.”

They never went back in to that room.

I DM for my brother and two of his boys. Last session we were taking a detour from HotDQ into Dungeon of the Mad Mage (because why not) for a downtime diversion. Exploring the first level, the PCs get to the room with the two pillars and the wild magic. Finally one of hte kids goes through the two columns. Roll the die, he turns invisible. The others just saw him disappear. So the kid decides to pick up one of the orc skeletons littering the base of the pillars and make it move around. Which totally freaks out the dwarf in the party (he's a paladin and also the kids' dad). So the dwarf throws one of his javelins at the skeleton. It goes through the skeleton's ribcage and lodges into the invisible PC. Who manages to hold in his groan of pain and not give himself away.

Then he went back through the columns and lost the invisibility. The group spent the next ten or so minutes repeatedly going through the columns to try to get the cool effect they wanted. The dragonborn (the other child) kept getting the "nothing happens" roll on the die. The paladin got the non-magic weapons turned magical and glow purple effect, then the invisible effect, then the magic weapons again. The other kid goes through a couple times trying to get back the invisibiltiy and succeeds before the dwarf ends the hijinx. Meanwhile my elf rogue is standing in the corner looking like Scar as the hyenas are being idiots while they're plotting Mufasa's death.

Same session, laterin the undermountain, they get swarmed by goblins and bugbears. Then the intellect devourers come out and one of them attacks the human ranger who's now lost invisibility since he's been attacking baddies through several rounds of combat. And fails the saving throw against devour intellect so the dwarf has to haul him back through the rooms of the undermountain they've been through and up the rope into the yawning portal.

Pretty epic session if I do  say so myself.

my group was playing through ghosts of saltmarsh recently. We were in the haunted mansion when my barbarian character decides he doesn't like haunted mansions. The mansion is not a complete mansion anymore.

So a little while back, we were on an adventure to get a pie recipe for a wizard (What? We were low level and its better than rats in the cellar). The catch was that this recipe was in the hands of some goblins that took over a bakery. There were dryads outback though, who we were interrogating for information. I, the wizard, roll high on my arcana check, and learn that dryads like flattery, physical beauty, etc... At this, our twenty strength, half-orc barbarian with muscles the size of mountains, decides to take his shirt off. Que a full minute of the dryads fawning over him and telling him everything we tell him to ask (because he has only 8 intelligence).

Playing through Curse of Strahd and they're sneaking around the crypt at the very bottom of Castle Ravenloft. The druid is the first to find "the curtain". What is the curtain? Only lawful good characters can pass through it. Otherwise, non-LG characters get teleported back up the stairs. My wife's celestial warlock was the only LG so she stepped through, only to find Strahd himself weeping over his mother's sarcophagus. That's where we ended the session, her character alone in a room with Strahd. Her reaction? "WHAT! AAAHHH!"

It definitely got me laughing.

My crew was 8 in total. one day i allowed people to do PvP. (Big mistake) They proceeded to fight over a wolf. One of our players, Garim (Using player name) started singing Kumbya. another player, Titan then proceeds to stab him with a pencil. In real life.

So we were level 4 or 5, and we found a bag of beans. This is in a library (in-game), by the way. So, we drop a bean. and we roll for the pyramid and the mummy lord. And we're like crapp were gonna die. But we still go in to fight it. So I'm a forge domain cleric and we have a gold dragonborn and a wizard and a rogue. Since its weak to fire, we use fire spells / breath weapon and totally annihilate it. There were two or three casualties, but I just healed them (cause they never actually died). and then we leveled up 3 times because of a random magic item. The rest of the dms campaign was totaly ruined.

Homebrew, the party is speaking with a bunch of guild and trade notables at a conferenſe. The famed crier Joseph D'Rogaun was there and couldn't give them a straight answer about the magical item theft because he wasn't personally involved, merely an ideological ally of the enemy party for the campaign. He taught them the importance of leg kicks, which for the mma inclined, are a favorite of a certain comedian turned MMA host.  Anyway, our monk learned the unarmed skill from him and then got sick of him talking about how the stones they're using in local castles make you crazy. Said monk threw a newly learned leg kick and crit 20'd so he just knocked him and they decided off with his head. Believe the half orc fastened it to his belt.

In the current session I'm in right now, there's a few small tidbits. But one of the most notable was an inside practical joke involving our resident ranger. This guy randomly fell asleep during our campaign to the point of it being in game. Every time the Ranger fell asleep, at any time, a random party member drew a dick on his forhead, giving him disadvantage on Charisma. And at one point, in multiple sessions, he ended up with about 5 ***** in charcoal on his forhead. He just recently found out and is so salty he's considering banning us from our own session.

This happened in a game I was DMing a few weeks ago. Exploring a haunted manor, the characters, an elf wizard, an elf rogue, and a drunken dwarf barbarian, come upon a deserted banquet hall, where all the plates are gold and stacked with golden food. Little do they know the food is actually normal, and covered in yellow mold.

Dwarf: I touch a plate.

Me: As you touch the gold, it explodes into a puff of spores, revealing that the "gold" was just a thin coating of mold. It burns at your nostrils and lungs. Make a Constitution saving throw.

He rolls. He passes. Aw, that was a cool trap, I think. I wish it did something. But I'm just opening my mouth to ask where they're going next, when...

Dwarf: I flip the table.

Now, I'm in shock for a moment, my mind racing, wondering how to handle this. Maybe this trap's going to work after all. I feel my face stretch into a grin.

Me: A cloud of spores fills the room. I need ALL OF YOU to make Constitution saving throws.

So I watched, trying to bite back my smile, as the dwarf succeeded his saving throw again, but both elves dropped. I'm pretty happy at this point: my trap's done its work and my players learned about chaotic stupid. The wizard was stabilized, but with each death saving throw the rogue failed, and each medicine check the dwarf missed, the players' voices got higher and higher. Then the last die was rolled...and the rogue died.

Boy, did I feel bad...but I also had a hard time not laughing.

One time we had a montage, in LMoP, of the characters drinking. It was on one of the stayovers in towns between adventure parts (I always made the characters feel like they had breathing room timewise.) Anyhow, our ranger, Smash, (slightly) short(er) for Shamash was a bit of a party dude and he was determined to make the taphouse that was formerly frequented by the Redbrands into his new haunt.

So, I'd have all of the players roll a constitution check and give them a little update on how the night was going. At first it was just having a good time and typical drunk nonsense. Then characters started getting really drunk. Then town's old prospector character (let's face it LMoP is basically a western) showed up in one vingnette. Then one of the characters was replaced by a pig wearing a hat (no one noticed). Then all of the characters were replaced by pigs wearing hats (no one notices). Then they were chasing the pigs around trying to reclaim various headgears. We'd still talk about the pigs from time to time.

I'm currently doing a homebrew.  The PCs are a Longtooth Shifter Rogue and a Dragonborn Ranger.  

Now I'm pretty lenient when it comes to character creation and backstory.  The Rogue has the hardcore, family murdered, last of the tribe thing going.  The Dragonborn...*sigh.  He is re-incarnated from another world after being hit by a truck..."ok, fine".  He woke up in this body.

Fast forward.  They are approaching a forest after hearing someone crying.  It turns out it is a dryad who is in dire need.  Golbins have overrun her Forrest.  The first thing out of the Dragonborn's mouth, "You are my Waifu!"  The shifter turns to him. "I have no idea what you just said, but my instincts are telling me to hate you".

I can foresee this getting out of hand. But, I'll make it work.

While running the Sunless Citadel, my party spent 30 minutes interacting with an orb that requires a WIS save (DC 15, gets higher if someone touches it) and causes characters to dash away from it for 3 rounds on a failure. After a long time spent running away before calmly returning to the orb, they all finally made the save (with increased DC) and became immune for 24 hours. They scooped up the orb, put it in the bag of holding and forgot about it.

Now, one PC is an unusual character, a Goliath Barbarian that occasionally transforms into a Kalashtar Sorcerer over long rests and vice versa (long story short: he's basically cursed ato transform from a genius to a brute, and his memories aren't shared between the two). He also happened to be the character in possession of the bag of holding and hadn't transformed yet during the campaign, having only played as the Goliath up until this point.

Two mornings later, everyone is eating breakfast and the Goliath hasn't come down yet. He had transformed from Goliath to Kalashtar in the night and we ran these initial moments away from the group for secrecy because they didn't know anything about this character yet. He dumped out the contents of his bag to make sure all of his things were there, giving me a wonderful gift by dumping out the bag knowing full well the orb was in there "because that's what my character would do." 

As the party was downstairs eating  they heard a thunk on the floor above, followed by a Kalashtar tearing out of the inn at full tilt. After a few moments, he calmly reentered the inn, sheepishly walked through, and went straight back up the stairs.

And that's how the party met this PC's other half. 

I have a couple of good ones.

I defeated a Frost Giant with lavender bath oil and glitter. I was playing a Kenku Arcane Trickster who couldn't keep his Mage Hand to himself around shiny objects. He collected keys and cutlery because they were shiny. At 3rd level the party walked into an apothecary and he stole a vial of sparkly liquid and some glitter. Turns out the liquid is lavender bath oil. Cut to an 8th level adventure and we are fighting a Frost Giant and his minions. We had alerted the giant so he had chugged a potion of Greater Invisibility and used a scroll of Haste. I had scouted on ahead and he started laying into me as best he could (I was lucky he rolled low a couple of times). As the party was catching up, I used my Mage Hand to pour the bath oil over his head and then throw glitter at it. Then the party caught up and laid into it while I hung back with my Hand Crossbow. That's how I defeated a giant with lavender bath oil and glitter.

I defeated a boss by fisting them while my friend rapped at them. I was playing a Half Elf Vengeance Paladin and my friend was playing a Bard. We confronted the final boss of the campaign set in Ravenloft at 12th level. She is one of Strahd's old flings that wants to get back in his good graces. While she was monologuing the Bard leans over and whispers in my ear "psst. Do you want to be a Giant Ape?" I nodded and once the fight started they cast Polymorph on me. I charged in, grappled the boss and started pummelling her. In the stat block, the attack of the Giant Ape is called Fist. So I said I was fisting her. The table was in stitches. When the Bards turn came, he roleplayed his Vicious Mockery and went into a full on 45 second a capella rap about how Strahd is stringing her along and that she's a cuck. It was amazing. The DM ruled that she critically failed her save without even rolling and that she had disadvantage on ability checks as well as attacks. So she failed to break my grapple and on my last attack I used Divine Smite and exploded her from the inside out.

I have to add one from my group of asshats...err players.  These guys consistently find loopholes and ways to exploit terrain and spells to their advantage (their current "favorite" is Fog Cloud, with Cloud of Daggers behind that, and then making the warforged Paladin take the brunt of beatings while the Cloud of Daggers softens up the baddies).  I allow most things as long as it doesn't directly contradict RAW.

So goes the following:

My players are in a cavern, that one side opens to the ocean (pirates were using this place to smuggle goods in to town), one small opening led to a cave network (this is where the party came from), and then another opening (just past an encampment) on the far side of the cavern to an archway that led up to the store "front" that the smuggling was happening at.  There were Reef Sharks nearby in the water that were making it hard for my PCs to get to the encampment.  The party Ranger uses Speak with Animals to get several sharks to grab and drag off the guards near the water.  I made the Ranger roll a persuasion check.  Nat 20, 19, 18, Nat 20 on the 4 sharks they could see... @#$%@#$...  I never would have imagined that she would roll that well...  Needless to say, the bad guys were down 4 guards, and the other guards panicked at the sudden shark attacks and fled.

Our Bard, who is an EPIC bard btw, challenged Azmodeus to a fiddle contest. The DM played the devil went down to Georgia while they made performance checks against each other during the song, and the bard won.

My group consists of 5 and we were running through a dungeon to recover a wizard. They had gotten to a point where they had to enter a temple and fight the yuan-ti boss and his minions. The group was a bit battered but had all super stealthed up with invis spells and pass without trace. The suprise kind of annihilated some of the minions but they were not looking good. Cleric turn comes around and he looks into the eyes of the boss yuan-ti and cats calm emotions. Boss rolls a 1 on the save. He successfully get the boss to 1) stop talking to negotiate 2) drops 300 gp in exchange for the wizard and 3) made the rest of the party angry for not letting them kill everyone.  

I just sat back and smiled as they walked out with the prisoner.  Note my group consists of my daughter and her friends so seeing them all rage at the cleric for doing something I thought was genius still makes me smile.

Back when i played as DM for the first time with my friends, i wanted to introduce them to the combat system, so I placed them in a inn, and introduced them to Their life line ( a characther i made in case things Got to hot for them) Anyway my selfmade hero challenged Our half orc for a test of might and control. So the hero put an apple on a young boys head, and asked the half orc to split the Apple without harming the boy. I asked him to roll a d20 and set the succes to 5, to make sure he would succes . He rolled A NATURAL 1 , ( his first dice cast Was a nat 1 , dindt See that coming) so that måde an uproar , so Before the adventure Even started,  they managed to start a race war, and Was now in the run from the law and locals. Not the story i had in mind , But i went with it and måde a homebrew Out of it.

The party Bard accidentally killed a guy by pooing on him.....Wasn't a quick death either. Everyone was too busy bertating the bard for taking a dump on a person to notice the guy dying in the corner.