Cthulhu was massive, easily larger than anything William had ever seen or fought. His skin was light brown, his arms were muscular. There was a blinking teal eye on each hand and a teal brain-like object embedded in his chest. He had no legs, as at about his stomach level his skin gave way to an exposed ribcage that stopped about where his waist would have been.

And his face... it was the thing of a nightmare. Glowing tentacles flowed down like a beard. He had five eyes on his head, two large, two smaller ones higher up, then a fifth sideways eye on his forehead. His brain was exposed, pulsating with energy.

This was what the Cultists had been working to bring back, and they had succeeded. This creature... no, this almost godlike being, was going to kill them all, and become the new Guardian of the world.

Unless William and his friends defeated him first.

He was not surprised to see Sid be the first one to go on the offensive, sending forth his Stardust Dragon and opening fire with his Snowman Cannon. The exploding projectiles, which had homing capabilities, seemed to curve towards Cthulhu's right hand and impact against the eye resting upon it, but when the eye closed, the projectiles just passed right through it.

Meg and Robyn both flew up and attacked, then William. He threw Daybreaks at Cthulhu's left hand, which was still open. The orange spears seemed to stay stuck into the hand's eye after impacting, each dealing constant extra damage, and they stacked up quite a bit. However, when the eye closed, the spears all just popped off. When the eye reopened several white energy spheres began popping out of the hand, hovering slightly upwards and forming a line, then all simultaneously flinging themselves towards him. He weaved in-between two of the spheres.

He then noticed Cthulhu's head eye open, it having been closed for most of the time so far, so he decided to throw some Daybreaks up there. However, a massive white deathray shot out, aiming a short distance from Robyn and sweeping towards her. She tried to drop downwards to avoid it, but still got hit, taking massive damage.

Right after the deathray dissipated, the head eye closed again. William realised that eye was probably going to be the one to focus on, since it was open the least amount. He saw Sid focussing his Stardust Dragon on one of the hand eyes, it flying around and around in circles around the eye as it dealt damage to it. Meg was using her Nebula Blaze, Robyn her Phantasm, all of them focussing down that one hand. William contributed as many Daybreak spears as he could, and the eye soon died, popping outward to reveal an open socket with mandible-like teeth inside. However, the eye then became living, flying around with assistance from its tentacles.

William read its label. 'True Eye of Cthulhu'. It didn't have any life numbers, and throwing Daybreaks at it didn't seem to damage it. The Eye cast a group of six white energy balls around it, then flung them all at Sid, which he dodged.

Around that same time he noticed Cthulhu's head eye had opened up – it was going to shoot its deathray again! It fired near Meg, and her strategy in avoiding it was to fly around it and then upwards. Her wings ran out of flight time, but she managed to avoid falling into the beam and taking damage by using her Rod of Discord to teleport down to the jungle floor.

William, Sid and Robyn at least had managed to get some decent damage into the head eye while it had been open, but it still had a lot of life left. Still, he felt that they could handle the Moon Lord if this was all it had. At least that was what he thought until the True Eye of Cthulhu uncorked a sweeping deathray of its own.

"Cactuses!" he heard Sid yell as its ray tracked after him. He managed to fly up and over the Eye and narrowly avoided getting hit, but this was an alarming development. The other two eyes were probably going to pop out True Eyes like this one after being destroyed. Cthulhu was only going to become more and more relentless.

William told his friends to focus on the head eye but leave the other hand on low health, so they'd only have to deal with the one True Eye of Cthulhu. This created some tense moments of pure attack dodging while waiting for the head eye to re-open, but before too long they brought down all of its life, and Sid whipped the remaining hand eye, sending his Stardust Dragon to finish it off.

That didn't kill Cthulhu – he now had three True Eyes of Cthulhu swirling around him, each firing volleys of white energy spheres and shooting sweeping deathrays.

"Its chest!" Meg shouted.

William saw the brain-like core embedded in the Moon Lord's chest was now damageable, with 75,000 total life. He turned his Daybreaks upon it. His friends likewise turned their respective weapons upon it too, but the three True Eyes of Cthulhu proved to be extremely relentless. At one point two of them fired deathrays at once, both aimed for Meg. She wouldn't have even survived if not for her Rod of Discord.

But they kept it up. It was hard going, but slowly but surely the core's health went down and down. Since it never opened or closed like the eyes, they could deal constant damage to it.

"We're almost there!" William shouted.

That was when a series of white energy spheres combined with a deathray sliced into him.

***

Robyn cried out as she watched William fall from the sky and land hard in the jungle.

She wanted to see if he was okay, but the Moon Lord was so close to being defeated. The best way she could ensure his survival was by taking it down.

Her Phantasm bow hummed as she fired arrow after arrow. The bow fired four arrows at once, and extra ghostly arrows kept on shooting out whenever any arrow made impact with a target, namely Cthulhu's core.

A deathray aimed at her, and she was forced to fly up and over the True Eye of Cthulhu to avoid it. She'd never even used wings before getting possessed – she'd had these wings, named 'Fishron Wings', equipped when she'd woken up, along with a number of other unfamiliar accessories and weapons, like the swords she'd nearly killed William with.

The Moon Lord roared, and suddenly disappeared in a flash of light. It reappeared right next to Meg, and hit her with one of his hands. She was knocked out of the sky, right into the path of one of the True Eyes' beams. She disappeared in a flurry of particles – she'd used a Magic Mirror to escape.

The Moon Lord then teleported again, this time near Sid. He wasn't so lucky – a tentacle shot from its mouth and clamped onto Sid. Then Cthulhu brought his two hands together, clapping him like a bug.

Robyn grit her teeth and kept firing for the Moon Lord's exposed chest. More arrows, arrows, more!

Another flash of light emanated from Cthulhu.

When it faded, Robyn saw Cthulhu's head was tilted at an oblique angle. His hands had spread apart, dropping Sid to the jungle below. He made another roar, this one sounding strained. His core began glowing, brighter and brighter, before –

KA-PLOWM!

The explosion disintegrated the Moon Lord's skin and arms, leaving a massive, empty skull and rib cage that fell down to the jungle below. She was sure she'd spotted some items falling down along with the corpsified debris, but that wasn't a priority in her mind.

William was.

She flew down to where he had landed. A frog seemed to be sniffing his armour, which hopped away when Robyn landed.

"William!" she cried.

He had just 7 life remaining. He'd been lucky.

"William..." she whimpered again, right as he coughed, his eyes shooting open.

"Robyn..." he said, but was interrupted by her kissing him hard and wrapping her arms tightly around him.

"We did it!"

William breathed a sigh of relief. "Yay," he said, then rested his head back and closed his eyes once more.