Both Robyn and the Lunatic Cultist attacked. Robyn pulled out a teal bow, and began firing – five arrows at once with each shot. William flew up to avoid them, and watched as she pursued him. He saw the Lunatic Cultist teleport forward and begin throwing fireballs at Sid and Meg, but he couldn't help them. He was going to have to hold out against Robyn for as long as he could.

He landed on the dungeon brick floor and began running, towards the wall, specifically to where he and Sid had been climbing at the very start of the battle.

Unbeknownst to Robyn, William had set up a plan earlier with the Steampunker. He had picked up some wiring from the Mechanic's bunker, as well as a spare wrench, and the whole time while he and Sid had been climbing earlier, he'd secretly been laying wire all the way up the wall.

He saw the place he had marked with a dirt block to indicate where the wiring was – wiring was invisible unless one were to hold an item that could interact with it, where it could be seen as a floating network that could be placed basically anywhere. He glanced up and saw Robyn was swooping down towards him, arrows firing from her bow.

He would have one shot at this. He whipped out a teleporter and placed it on the ground, then a pressure plate on top. Robyn wasn't able to turn in time, and she landed right on the teleporter and instantly disappeared in a spray of yellow particles.

William took a second to breathe – his plan had worked! – and he stepped on himself.

He was teleported to the desert – the wire trail had been laid all the way there, to another teleporter placed out there. Far away from the Dungeon, to ensure he'd have Robyn to himself.

He smashed the teleporter with his pickaxe, the item rushing into his inventory, and turned to face her, who looked genuinely bewildered for the first time ever since being possessed.

She turned to him.

"An impressive trick. But your friends can't save you from me out here."

"That is a risk I'm willing to take," William said.

"Why would you take such a foolish risk?"

"It might be reckless. But nothing's stopping me from getting you back."

She roared and pulled out two swords, then lunged forward.

***

The Lunatic Cultist, dressed in his hooded blue robes and white plague doctor mask, had a wide array of magical attacks. Homing fireballs, icy balls that fired ice shards in all directions, an electric sphere that shot lighting at them. Sid and Meg were constantly on the move through the air, constantly firing at the Lunatic Cultist as he teleported around.

He suddenly disappeared, and a large yellow engram with a triangular pattern inside expanded out. Several illusions of the Lunatic Cultist rotated around its circumference, before coalescing into three of them.

"Musket balls," Sid muttered, as the Lunatic Cultist's now tripled firepower shot out at him.

His jetpack blasted him upwards, out of the path of the fireballs he shot, then he dodged to the side to avoid the lightning. At that same moment the three Lunatic Cultists all raised their hands, and a translucent, wyvern-like creature named the Phantasm Dragon was summoned forth. It swooped at Sid, its head slamming into him.

Meg got its attention with some blasts from her Razorpine. She mounted her Witch's Broom and began soaring straight upwards, the Phantasm Dragon chasing after her. She held out her Nimbus Rod and kept summoning clouds directly above her. This trick she'd once tried on a Wyvern back when they'd been collecting Souls of Flight – as she and the Dragon ascended, the raindrops from her nimbus clouds constantly pierced the Dragon, quickly shredding its health away. It soon disappeared in clouds of smoke, and she dismounted her broom and fell back down to rejoin the battle.

Sid snapped at the Lunatic Cultist and his illusions with his Kaleidoscope, his Terraprisma constantly stabbing at and twirling around him. But the Lunatic Cultist only dialled up his attacks, summoning lots of dark purple skulls in the air named Ancient Dooms that split into four purple energy balls that moved in different directions. Before too long he did another illusory energy ritual, increasing the number of Lunatic Cultists visible to five.

"We've got to take him down quickly!" Meg shouted, but she was hit by a volley of starry projectiles, then the Lunatic Cultist followed it up with a stream of lightning attacks that she was not able to dodge.

She fell to the ground and lay still.

***

William raised his Terra Blade just in time to block Robyn's first swipe with one of her swords, which was bright orange like a pumpkin. She swung with her other sword, which had a blade that was a gradient of pink to magenta to yellow, and William dashed to the side to avoid the pink starry projectiles that flew down from the sky. That sword was like a Starfury, except much more powerful.

He swung his Terra Blade at her, sending energy sword after energy sword at her, but she was able to knock each one away with her own blades. She then dashed forward and managed to land a blow on William with her orange sword.

He pulled out a second sword of his own – the Influx Waver that the Martian Saucer had dropped – and locked blades. He jumped to avoid the homing pumpkin that shot after him from the sky and then dodged some more star projectiles, swinging both his blades at her, firing volleys of both green and electric-blue blades.

While he was in the sky she pulled out a rainbow-encrusted bow and fired volley after volley of rainbow arrows that reminded him of the Empress of Light's attacks. He dodged to avoid them, then swooped down at her, holding out his Starlight to stab at her.

He managed to land some blows with it, but at the same time she hit him away with her orange blade. More homing pumpkins shot after him, which he hit with his sword to destroy, then he raised his Terra Blade and Influx Waver to block her next swipe with both her swords. However, he was not able to avoid the starry projectiles that shot down from the sky, and he was pelted and fell backwards onto the sand.

Then he had two swords held to his neck, crossed over each other. Robyn stared down at him with her cursed eyes, a tight frown across her face.

This is it, he thought, as he stared up at her and accepted his fate.

***

Sid roared and snapped his whip at the Lunatic Cultist, sending his Terraprisma after it. The Cultist retaliated by summoning forth another Phantasm Dragon and some large golden tentacle-ridden heads named Ancient Visions. He whipped at them to get the Terraprisma to get rid of them, then got out his Tactical Shotgun. He still had Chlorophyte Bullets left over from his fight against the Empress of Light, and knew that they'd be useful for hitting such a small target. He fired, and fired, and fired again at the Cultist, more and more bullets zooming to hit their mark and lower his health, but the Cultist just laughed and dissolved, summoning another yellow engram with the illusions all rotating around it.

He fired at the illusions, and was shocked when his bullets hit their mark, causing the engram to shatter and all the illusions to shrink inwards. Now the Lunatic Cultist was alone.

"Get him!" Sid shouted as he snapped his Kaleidoscope at him. His Terraprisma all rushed forward and hacked and slashed at him. The Lunatic Cultist kept casting his spells, but even Sid could tell they were getting more and more frantic and desperate.

His health was soon brought down to almost zero, and he fell to the ground in a pile of blue clothing.

Sid landed on the ground and pulled at the Lunatic Cultist's body, turning him over. His head moved, the beak on his mask pointing at Sid.

"You won this battle..." he coughed, speaking for the first time in the entire fight, with a low, echoing voice. "But even if you slay Cthulhu as well... you're only leaving the world open to even bigger threats..."

Then he vanished into dust.

All that remained was an ancient-looking item that zipped into Sid's inventory.

At the same time, the sky around them turned bright magenta.