Reincarnated With A Summoning System

"Oath Breakers, find and kill the Lieutenants. Both of you go together since they've got a level advantage and their defenders." Cain instructs the last two Legendary Demons he's not merged with. 

They disappear instantly, and Cain hopes that their assassination skills will be enough to take care of the Lieutenants. If the big boss is here, he should have brought both of them unless he was arrogant enough to leave one behind at home to run the city in his absence.

If he organized this attack himself, he might have been gone a while arranging all the mercenaries, which would be great for them, with one fewer dangerous targets and a reduction in total summons. 

Cain had just reached the west wall when a cheer went up in the East, lord enough that even over the roar of the Cannons, it carried across the castle. Hopefully, that was a sign that an important figure had been killed. There were a lot of attackers coming that way. 

"Summon me again," Vala calls out to Cain, her voice audible in his mind despite the distance. Cain immediately summons her, the twin Demons appearing at his side with a roaring laugh before running back to her position along the East wall. 

He's not sure what that's about, but she seemed happy, which is all that matters. 

"Need a fresh Summon." Laura also requests a moment later, Cain again calling his companion to his side, the Dragons flying away without a word. 

"Me too," Evangeline adds in a sad tone. She was the first into combat, though, so she didn't do too badly. 

After the Companions are done with, Cain calls a fresh batch of Supporters to assist them. Many have fallen in battle, and the rest are getting low on mana, so it's best to call them back a few at a time, so no area ends up totally empty of Snapping Turtles and healers for long. The Legendary Summons are incredibly hard to kill, which his helping to keep the enemy away from the walls. 

The western front is relatively quiet compared to the others. There are enemies out there, but they've stopped beyond the sand. Only a few probing attacks have been sent and met with a hail of Cannon fire after the first waves of giants were dealt with. They must have sent most of their summons north and south to help the attackers because Cain's combat log is nothing but a wall of death notifications. 

To keep them from resting and regrouping, Cain is sending waves of Demons, Wrath Bringers and Lesser Plague Knights who were chosen for their durability, into the Western Front attackers. Joined by a pair of Kone clones, with their companion Dragons and hordes of Turtles, the fact that the Western Front has mostly remained out of sight and Cannon range is not saving them. 

On the other fronts, the cannon fire is constant, the booming of the big guns and whistle of arrows from the Hwacha is a steady beat, as if the battle has its own rhythm, or heartbeat.

Depending on adjustments needed and mana supply, the magical Cannons can fire every six seconds or so. A thousand total rounds a minute being fired almost sounds like a hail storm at some moments, a crash of Thunder at others when a group of them coincidentally fire at the same instant instead of slightly staggered. 

The number of Forest Dragons and Supporters is getting low again, so Cain calls a fresh batch of supporters all at once to save mana, the diminutive forms of the Summoned Beast Masters climbing on the backs of the Su clones, ready to bring out more Snapping Turtles and spread as much healing as they can. 

Gillibrand must have thought they'd killed someone important because the moment the Snapping Turtles disappear, the western front charges. Unfortunately for them, all the Supporters are currently here. 

"Two supporters to each of the other fronts, don't leave them without Turtles," Cain shouts, turning to see the situation and calling another wave of demons to meet the charge. 

The East wall is still holding well. Mythryll has joined Misha on the wall, her control abilities slowing the attackers while the summons rip them apart. North and South are now fighting near the walls, with some needing to be knocked back off in the northern regions.

In the South Sora head just sent out another Illusionary Army. The enemy now mostly understands that they're less dangerous than they look, but for the low level attackers it doesn't matter. The Illusionary Seraphim are real enough to do significant damage to them, and there are so many ground troops that the fighting in the south becomes a stalemate as the enemy struggles to clear themselves room to move. 

It's a losing battle, more summons are incoming, along with Supporters with full mana. By the time they've dealt with Sora's chaos, they'll be facing even more of a threat. 

There seems to be an additional Summoner here, at least as Capable as the Lieutenant. 

Wave after wave attacks Cain in the west, whittling down the defenders and Cain's mana despite an abundance of Totems from the Flame Sisters that Maggie stationed all around the castle.

The enemy Summoner has called a genuinely savage form of Demon on the western front now, a high level Greater Golem that easily keeps up with their Epic Quality opponents before being slaughtered by the Legendary Turtles, so Cain decides to add it now, thinking he might swap some of his Golems around. 

[New Forms cannot be learned while Quest: There Can Be Only One is in effect] 

Crap. Well, at least that means Gillibrand won't be calling for a load of Kone clones and creating a mirror match with an added dose of confusion. 

The south walls are cheering now, and Cain can see the sand is suddenly mostly deserted, where a moment ago, they were in danger of being overrun. The Oath Breakers must have killed another Lieutenant. With the East and South now facing far fewer summons than a few minutes ago, that's Cain's cue to get to work before their replacements can make it from wherever Gillibrand is to the other fronts. 

[Oath Breakers, take me to Gillibrand. He needs to die before he can replace those Lieutenants.]

In a single stomach-turning leap through the void, Cain faces his rival Puppet Master. Gillibrand might be twice his level, but Cain has [Might of Many] and the [Five Tiger Spear] on his side. 

Gillibrand's Bodyguards, a pair of wolfkin Rogues, intercept Cain as he appears, thwarting the first strikes, but one dies to the spear. At the same time, the other falls to a combination of the Scimitar and the Area Damage effect from the Oath Breakers Cain is merged with. 

The Puppet Master himself is fine, losing over a quarter of his health, even with his level advantage and merged summons. He doesn't have Legendary Summons though. Not even Epic ones, as far as Cain can tell. He certainly hasn't gotten them from his class skills yet. 

He also isn't a melee fighter, constantly trying to retreat to be able to fire his bow, but Cain is all over him, the increased speed from the Oath Breakers, as well as [Cloud Dancing] making him impossible to escape from.

The two he isn't merged with are doing their best to keep Cain safe from the army around them until Gillibrand panics as a spear thrust grazes his neck and calls all his Lieutenants to defend him. That would be the greatest, if not final, mistake of his life. 

Three new humans appear and Cain turns his attacks away from the Puppet Master, chopping into the Lieutenants with rapid swings of his Scimitar before he uses Cloud Dancing to leap up high enough to spear a giant through the heart. 

Gillibrand seems biased towards certain summons, his Lieutenants are all humans, nothing unexpected or tricky, and certainly nothing like Laura and Sora working together to create a flying headache for the lower level attackers who were intended to seize defensive assets.

The increased damage effect of the Spear takes effect as the Giant dies and Cain gives a happy smile that makes Gillibrand's blood run cold. 

The increased damage applied in that strike should make every hit a single strike kill if it weren't already. A group of healers, summons by Cain's estimation as their level matches the Puppet Master's, is frantically healing him to full health after every blow Cain lands. But the damage has stacked again, and it proves too much for them to bear, all six of them die to the area effect caused by Cain's next strike against their master. 

Gillibrand himself is in terrible shape, under a quarter-life, his mana exhausted from the need to bring back summons to defend himself, thanks to his lack of melee combat skills. With no Shamans left alive in the area to create a mana totem, his plight was just getting worse and worse.

He falls to his knees in exhaustion, clearly knowing what comes next. "Do it then. I've had a good run, almost since the very beginning of the System." He says wearily, and with a silent swipe of a Scimitar, Cain removes his head from his body. 

Now, for the critical part.

[Puppet Masters cannot be Summoned] 

Cain roars in anger, mimicking the Tiger whose form he had only recently taken "Sonofa... that dirty, low down, good for nothing spawn of a discount whore." 

The Oath Breakers give the jumbled expression of rage a round of applause, while the few enemy targets still alive in the area stare in horror at the loss of their leader. All the summons are gone, except the few that their surviving mages and Druids called, and the change in power balance was too sudden for them to adapt. 

"I'm so not done with this guy yet." The icy voice coming from Cain causes the few who were still brave enough to approach him, hoping for a kill while he was distracted, to turn tail and run for their lives. 

[All summons. Clean up the battlefield. Gather any who are smart enough to surrender, and we will deal with them afterward.]

Cain looks down at the body of Gillibrand, and a note of inspiration strikes him. 

[Eternal Solace Denied] 

The look of horror on the man's face after his head reattached itself to his body and his heart started beating again with a sudden lurch is priceless. 

"What have you done? This isn't life or even undeath. The Unholy rituals a necromancer performs don't come close to being this wrong. His summons don't have their minds intact." 

"I was a bit unhappy, you see. Puppet Masters cannot be Summoned. Even after I killed you and ended that Quest, I still couldn't Summon your clone. But now I have you in person, and I can vent my frustrations."

"Please don't." A gentle voice comes from the distance, carried by magic, and Cain sees a dark-haired human woman in a red gown flying in on a shining white Pegasus. Two more additions to his collection. Oh, she was already known. Gillibrand must have had them recorded. 

"And why not?"

"Release him to me, and I'll make sure he doesn't ever try such a foolish thing again. We've been together for over a century, don't make me live without him."

"Over a century together, and you didn't see this coming? Surely a few years penance is in order?"

The flood of deaths in Cain's combat log has all but stopped; the battle for the castle is essentially over with only cleanup left and hostages to deal with. 

The woman, an Arch Priestess by class, and Momo by name dismounts and kneels. She falls to her knees, face to the sand, imploring Cain. "If you wish, I shall whip him daily until he learns, just please, release him to me."

[Yes, RELEASE him to her] the voices of the Oath Breakers in Cain's mind laugh, and Cain can't help but smile at their marvelous suggestion. 

"Alright, Momo, I shall release him, and you shall whip him daily until you're sure he's learned his lesson. To never again accept that quest. I won't refuse him the right to defend himself, but I don't want to ever hear of Gillibrand attacking anyone."

The woman nods eagerly, seeing hope that her beloved won't be kept from her. She's high enough level to resurrect him, but as Cain's Supporter, there is nothing she can think to do short of killing him herself to bring him back, which might not be possible with Cain nearby and protecting him. 

"As you wish, he is free. A punishment and a gift. Your beloved is yours now; treat him gently; he's fragile."

The way Cain smiles makes Momo immediately check Gillibrand's status, seeing that he is now a level 1 Puppet Master. That's, well, she doesn't have a word to describe what she's feeling, but a smile slowly spreads across her face as she considers the possibilities. 

"Is he truly level 1? A freshly transferred Puppet Master?" She asks. 

"Yes, and he will need to work his way back up however he can. Any skills he had gained from classes he previously held and most likely from books as well have been erased." Cain verifies. 

Gillibrand breaks down at this point, silent tears of anguish falling to the ground as he realizes centuries of his life have been removed from him. In the face of death, he had hopes of resurrection. In the brief moments of slavery as a Supporter, he had hopes of freedom. But now, as a level 1 Puppet Master with no skills and only his starting Stats, what can he hope for? 

Gillibrand had followed a path of power, advancing his class from Politician to Cult Leader to Puppet Master while having others fight his battles and relying on his abilities to influence the minds of the crowd. Now that's all gone, and he's nothing but a level 1 Summoning type class. No more mass mind control, Dominating Aura or anything else he has relief upon for centuries to maintain his political power. 

"It's not so bad, darling. Come home with me and I'll dress you up, feed you well and play with you all that you'd like. Doesn't that sound wonderful, my pretty little pet?"

With that, Momo loads Gillibrand's crying form on her Pegasus and flies away, leaving Cain speechless and the Oath Breakers joking about how his life of suffering had only just begun.

Who would have guessed his wife was a closeted Sadist? Perhaps he always knew, but his skills kept him from being her target?