TL;DR at the bottom.
As a DM, one thing that I love about D&D is how creative people can be, and my party is one such group. Some backstory before we get to the good stuff; I started my first campaign as a DM at the beginning of 2020, but since it was all in person, we had to stop because of the Pandemic. So after finding out about Roll20 and Discord thanks to a group called the Unexpectables on YouTube, I started hosting a game in mid-April, and started off with session zero. I told them I had a lot of homebrew in mind and that I was new to DMing, but one of the players was formally a DM himself, and he helped me with whatever I needed.
I wanted to start things off at a homebrew level 0, were the party had some detriments, but were giving a free starting feat for their troubles. Our cast of characters includes: Krog, an Orc Barbarian with the Tavern Brawler feat; he was the comedian of the party thanks to good RP with his low Intelligence score. Riknar, the Half-Drow Paladin with the Shield Master feat; he was the long time DM, and a bit of a min-maxer. Scraps, the Goblin Rogue with the Sharpshooter feat; his back and forth with Krog in “chaotic” acts kept the party on their toes in otherwise peaceful scenarios. Scarlett, the Tiefling Sorceress with the Elemental Adept: Fire feat; she was very new to D&D and was helped by her friend, the long time DM, to make a character that was equally helpful in offensive and defensive magic. And finally, the center of this first story, Snow, the Tabaxi Artificer with the Mobile feat; she was kicked out of other D&D games by the DMs because she pulled stuff that, while not rule breaking, were so far out the box that her former DMs “wouldn’t let her play the way she wanted” as she put it.
At the time of this story, the party was at level 3, and in the middle of an escort to bring weapons to the resistance force of a country in the middle of a civil war. On their way, they stumble onto a small village that was recently ravaged by an ancient black dragon, but its age was unknown to the villagers. This was supposed to be a plot hook for the group to come back to once they were at a higher level, as the dragon would terrorize the country side with its army of kobolds to prevent peace in the country. The village head approached the party about this, “That beast has taken our children as food for itself and raided our storehouses for anything else it could. Please help us great explorers, we’ll do anything we can.”
Most of the party was taken aback at the idea of facing a dragon at their current level, as I thought, but Snow simply stepped forward, “Are you willing to lend us your forge, some iron, and your finest blacksmith?”
“Uh… yes, of course.”
“Then I promise that I can make a weapon to defeat that dragon; just give us one week to finish it, and lodgings during that time.”
I was confused by this gesture, but simply went along with it, “Okay, make a Deception check.”
“But I’m not lying.”
“Uh… alright, Persuasion then.” She succeeds on the roll, and the rest of the party go along with it, partly for the free rations, but mostly out of curiosity.
With Snow’s proficiency in smithing tools and a few good rolls, including a nat 20, she finished the device to defeat the dragon in five days; it was described as being two unique metal cages: one being 1 cube foot, two large loops on top opposite of each other, six pin holes in the metal on top that lined up for three pins, eight clamps just inside the top, and an open top with no door. The other cage could barely slide into the first one, had a simple door on the bottom built less robust than the rest of it, the same two loops on top, and a pair of pinholes that lined up at the bottom. She described that there were frills at the bottom of the smaller cage that, after being put in the first one, you could put the two side pins in, and the cages couldn’t separate, and that the remaining pinholes would line up if the two cages were pulled apart while the other pins were in, allowing the third pin to enter, and lock the two in place.
The party was still confused, but proceeded to follow her example. They left the village and carriage behind, their delivery of arms to be completed once they had returned. On their way to the caverns the dragon dwelled, Snow spoke up about her plan, “Once we find the dragon, I will need a bit to set up the device, and once we lure it away from its horde, Krog will throw it as hard as he can at the beast.”
It was at this moment that the party understood her confidence, but Scraps still needed to ask, “And what if it doesn’t work?”
“We only have one chance, and if it doesn’t work… we die.”
“Fair enough, long odds pay big.”
Krog then chipped in, “So, we go, dragon come, I throw, we get money?”
“That’s right, the dragon’s horde.”
Once the group arrived at the cavern, they began slowly going through the corridors one by one, defeating the kobolds serving the dragon. To reiterate, I planned on this dungeon being for a party three times their level, and I wanted them to know that actions had consequences, so the difficulty of this area was unchanged. Despite this, they managed to work their way through, killing nearly every kobold underling save for Drax, who was young and aspired to be a powerful warlock, a story for a later time. They found the dragon, and Snow began to set up her device, and, for context, I rarely check on character sheets unless I think they’re cheating, or playing as them as they were gone, so I had no idea what she had planned, as the rest of the group continued to scout the area.
Snow finished her device, so Riknar and Scarlett began a back and forth argument to stir the dragon, with Scarlett starting off, “I’m telling you, this is the wrong way.” like the two were a married couple arguing over directions. They woke the dragon, and with a few deception and persuasion rolls, they lured the dragon towards Snow and Krog; the device now was wrapped in a sheet, with a string and rope coming out of the package. The string was tied to the middle pin, while the rope was fed through the large loops in a way that, when tugged, would cause the two cages to slam into each other. The dragon approached the opening of the chamber, so Snow called out, “NOW!!” and Krog threw the device. I look to Krog, “Okay Krog, are you trying to hit the dragon or just getting it close to it?”
“It doesn’t matter, I have proficiency in Athletes and Improvised Weapons.”
“I need to know for damage.”
“Uh… to hit.”
“Roll your Improvised Weapon.”
“You hit, roll 1d6 plus Strength; the device is a bit heavy.”
Snow interjected, “My held action goes off now right?”
I nodded, “Indeed it does.”
“I first pull out the pin using the string, then I pull the rope to put the two cages together.”
Do to the nature of the situation, I decided to mess with her a bit, “Did you lubricate the rope at all.”
“Then make an Athletics check” Snow had only 7 Strength, a minus 2 modifier, but the DC was only 5. She succeeded, and I’ll never forget the question she asked, the question that answered all our questions, “Do you know what happens when you put a Bag of Holding into another Bag of Holding?”
The chat went silent as we realized what she just did; each cage of the device had one bag each, and the clamps held one open and out of the way for the other cage to slide in. I simply asked, “Wait, how do you have two Bags of Holding? I know that you can have one as an Artificer, but were did the other one come from?”
“Well, I have two infusions that I can activate each day, so I got rid of Alchemy Jug.”
“You can’t do that; each infusion can only be used once per item.”
“But two of my infusions are Bag of Holding.”
“What?” We all took a moment to look up the RAW rules, and sure enough, you can have two of any Magic Items you want, and since I didn’t have any homebrew against it, she was free to do it. The only problem was that there was a homebrew rule that she must have either not read or forgotten about; see, I had planned on giving the group a Handy Haver Sack later on, and I knew that the group might experiment with a “Nuclear Option” eventually, but not this early on. I sighed and said, “You watch as the device becomes a singularity to the Astral Plane, and the Dragon let’s out a horrid roar as it’s pulled in. Snow, Krog, the two of you are too close to the portal, and feel it pull you towards it, both of you make a Strength Saving throw.” Krog passed easily, but Snow rolled too low to pass.
Before I could say anything, Krog spoke up, “Wait, can I help Snow since I’m right next to her?”
“Sure, but you need to roll again for disadvantage.” He rolled a 10, just enough to pass, so I decided to mess with them some more; I respond, “As Snow is lifted off the ground and pulled towards the vortex, Krog grabs her by the wrist. The two of you are being pulled towards the void, and Krog, you feel your grip slipping. So, you two, what are your last words?” The chat was baffled, but understanding.
Krog was the first to speak, “Krog sorry, can’t hold on.”
Snow was a bit more disappointed, “Let me go!” she screamed, “I want to wriggle out of Krogs grip.”
I sighed, “Okay, you need to roll competing Athletes checks.” Krog rolled 13, but Snow rolled a 15, so I made a d100 roll to determine the aftermath. With a 9, I sighed, “Snow wriggles free from Krogs grip, and floats to the opening between planes. You all watch as just as she’s about to be lost forever, the pathway closes, and she falls to the ground.” The party cheered before I continued, “As you all approach Snow, you see a puddle of blood on the ground; Snow’s left arm was in the portal as it closed, severing it and trapping it in the Astral Plane.” The party was a bit distraught, but Snow revealed that since her subclass was Armorer, she could use her armor as an extension of herself, replacing her lost limb. The party collected their thoughts, and went through the dragon’s horde; 10,000 gp in jewels and precious stones, bones for some magic equipment and potions, and three rare magic items.
After a long rest near the horde, Snow made another Bag of Holding to put most of it in, and by the session’s end, I ruled that no two infusions could be identical again.
TL;DR: Artificer uses two of her infusions to create a device that can put one bag of holding into another, sending a dragon and her arm to the astral plane.