Sometimes, a kind gesture can lead to the craziest encounter a party can face.
I am the DM for a homebrew 5e setting, which I had been running for nearly six months. The Party is made up of three players: Zrakris – a Black Dragonborn Vengeance Paladin, Knacker – an old Tiefling Necromancer, and Buxton – a Human Sorcerer using a homebrew Oceanic-themed Origin. The party is around level 16.
For background context, the Party had just returned to the Capital after slaying Knacker's old cult leader, Monteur. Monteur was once involved with the BBEG of this arc and the party sought him out to get information and put him to rest. However, though they were successful with their endeavors, the BBEG they were preparing to face was not the true final boss. Earlier on in the campaign, I asked my players if they wanted to go the full length of the campaign or if they wanted to split it up into two parts and come back to it later. They chose the latter. So, I made the final boss for this arc the finale. Or so we all thought.
Zrakris, our Paladin, had picked up a Deck of Many Things and had used it amusingly throughout the course of the story. (He sent a snobby cleric away with the Void card) One of the cards he drew was the Moon card. For those of you who have never drawn this card, it gives its user 1d3 Wishes. He had three wishes, and was down to his last one.
The Party returned to the Queen, who had sent them on their mission. She was a young Wood-Elvish girl who took the throne after her father perished on a trip to a war monument. His body was never recovered. As the party was discussing their next plan of action with the Queen's Goliath Paladin bodyguard, Zrakris was chatting up the Queen. Casually, Zrakris told her: "I wish your Father was here." At first, we thought nothing of it. The Dragonborn had served under the King before his death, and we thought he was just feeling sentimental about his absence. Oh, no. He was using his last Wish to bring the King to the war room.
Now, above game, I knew what had actually happened to the King. In an evil one-shot, Knacker's player, who played a Fallen Aasimar Vengeance Paladin, had aided the Goliath bodyguard in dispatching the King. The King had been searching for a member of his royal guard that had supposedly fled to the Elemental Plane of Fire after stealing a powerful sword. The portal to this Plane was beneath the war monument, and the King planned to retrieve his guard and the sword himself. Once the King passed through the Portal, the Goliath bodyguard and the Aasimar struck down the support that kept the Portal open, trapping the King inside and allowing them to puppet his daughter who would take the throne in his abscence.
So, Zrakris wishes for the King to be present with the Party. I describe as a portal spewing hellfire opens up at the far end of the war room, and a knight clad in smoldering full plate steps out, wielding a burning greatsword in his left hand. Unbeknownst to the Party, the King had survived his encounters within the Elemental Plane of Fire, but had become possessed by the armor he was forced to wear. A burning shell of a man he once was, the King's mind was contorted and his will suppressed. Angry for being pulled from his duties against his will, the King attacked. His first target was the Goliath Paladin, the closest person to him. Within a single round of attacks, the King brought the Goliath down to just under 30 HP – from his max of 161.
I look to the Party, a malevolent smile on my lips. "Say hello to the Final Boss, the one we decided to keep for later. Let's roll for inititative." The Party was obviously awestruck and horrified at what I just said, and I couldn't blame them. This came from left field and was all because Zrakris thought he would be able to bring closure to the Queen.
Taking what actions he could, Zrakris casted a 5th level Circle of Power, taking 5d10 Necrotic damage due to the effects of casting Wish. He was hoping to provide what support he could, mainly since his Strength stat was currently at 3. Next, Knacker decided to pull out the big guns and cast a 9th level Prismatic Wall, creating a dome that surrounded the King. The King failed his save against being blinded. After that, the Goliath took the Queen and began to flee, bringing her to safety and to gather more men to help stop this threat. Buxton was last on the initiative, and casted a 3rd level Tidal Wave. I ruled it that the spell was encased within the Prismatic Wall, making the King trapped within a fishbowl.
Next round of combat began, and I ruled that each layer of the Prismatic Wall would take full movement to get through. This means that the party has seven rounds of combat to gather what they need to defeat the King. The King takes his full movement and gets through one layer of the Wall. Zrakris took the time and healed himself with some of his Lay on Hands ability. Knacker began to cast Magnificent Mansion as a backup plan incase the party needed to escape. This would take a minute, so the old Tiefling would only have 3 rounds after the King escaped to complete the Mansion. The Queen and Goliath had fled by this point, removing them from combat. Buxton's turn, and oh boy did he have a plan. Using his sorcerous magic, he casted a Blink Spell as a bonus action to enter the water-filled dome. He could breathe underwater, so he would be alright. However, Buxton failed the save against being blinded by the Wall, but manages to cast a 5th level Maelstrom.
So, let's just asses what just happened. The King must make it through each layer of the Prismatic Wall, taking 50d6 of elemental damage types total as he makes it though each layer. He also has to make both a Dexterity and a Strength Save to resist damage from both the Tidal Wave and Maelstrom spells; in addition to either falling prone or being dragged 10 feet towards the center of the Maelstrom upon failing both of those spell's saves. This also means that Buxton has to make the same saves for his own spells.
Knacker's Player put it perfectly: "Buxton, you are a blind man trapped inside a killer washing machine."
Indeed he was. Buxton failed every single one of his Strength Saves to resist the Maelstrom spell he casted. In addition, he was completely blind, not knowing where the King was, and the Blink Spell had him popping in and out of combat every round. By the time Buxton finally emerged from the killer washing machine, he had 24 health from his original 140 HP, all of which was self-inflicted.
Speeding up combat, the King also emerged from the Wall, still blind. I rolled for which way he would move, and he would attack whatever he came into contact to. This happened to be in the direction of Zrakris, our Paladin. The King swung wildly at him, cleaving through his health and with a lucky critical hit, cleft through Zrakris' shield and shield hand. Zrakris retaliated with one final smite, dealing solid damage to the King while dealing himself 4d10 Necrotic damage due to the effects of Wish, putting Zrakris into Death Save territory by his own volition. Knacker cried out in shock, fearing for his friend but unable to do anything unless he stopped casting the mansion. He casts Shadow Blade as an 8th level as his bonus action – just in case. Hearing Knacker's cry, the King began to stalk towards him.
This fight has lasted for nearly three hours and we just hit round 10. Buxton is no longer blinded, and now being able to see the King once again, decided it was now or never. Buxton raises a pointed finger at the King and says: "I ask, nay, I command you… DIE!" Buxton casts his 9th level Power Word Kill. I ask him: "You target the King, correct?" Buxton's player confirms. I then describe the scene.
"Buxton, you point your finger at the King and command him to die. Around you, you sense your ancestors, all doing the same. They understand the gravity of the situation, and they wish for this to end."
I describe as the King slumps forward, his life now truly ended. However, as the Party finally takes a sigh of relief, he stands back up. I love doing multi-phase bosses, and the armor was technically its own seperate entity. Now top of the initiative, the armor has a choice to make. It either kills the creature before it, or saunter over and slay the creature that killed its flesh puppet. I rolled a d20 – ten under it attacked Knacker, eleven or higher it attacked Buxton. It rolled a 14, so Buxton it was.
As it began to walk over to Buxton, fury and malice literally burning from it, Knacker was given an opportunity attack. He managed to hit its high AC, and drove the Shadow Blade through the smoldering helmet, dealing 21 points of damage – a single point over the armor's HP. Knacker rode the body down to the ground, the innate psychic damage of the spell diffusing what semblance of life the armor had. The guards that the Queen had gathered finally arrived, and they took care of the situation. The Party was rewarded for their efforts, and they returned the kindness by reviving the King back to life with his sanity intact. Weak but humbled, the King thanked them for freeing him from the clutches of the armor. There was a sweet reunion between the King and his daughter, and the Party could now take a moment to sigh in relief.
At this point, the table is estatic. They managed to overcome a seemingly impossible challenge, thanks to some creative (albeit somewhat suicidal) magic. After the fight, the Party survived their wounds and continued the story, wrapping up the final arc in another awesome combat encounter.