"You remember how Tabula made Rubedo, right?" Rei smirked, possessively yet affectionately pulling Solution closer and surprising her by kissing her cheek.
Ainz, trying to ignore the affectionate gesture, nodded, "Umu... he used world item to create the golem core for her, giving her incredible core stats. I don't know about the full process though. He never shared."
"Well... he did with me." Rei chuckled, remembering it took him only one hundred thousand for that information. Honestly, he would have given that money to Tabula anyway as the man had a solid plan for a business, and not investing in him would have been a shame. "It... doesn't really matter anymore." Rei shrugged off Ainz's questioning look, "What is important is that it showed the NPCs can be strengthened via World Items if you use a certain exploit Tabula found by a sheer coincidence. I just went further with that idea." Rei admitted.
"Wait," Ainz's head snapped towards Solution, "You want to tell me she is like Rubedo? She was made with World Item as a base?" He asked incredulously. From what he knew, Rubedo could have been created that way because she was a weird mix of golem and angel.
"[Potential to Reach the Heavens]" Rei stated, "It is a less-known World Item that allows a level 1 NPC or player to change the effects of one item into a passive skill by destroying that item. It's like getting one more permanently filled equipment slot. Not that many would bother since it did require you to be level 1 and you know how hard Exping in Yggdrasil was."
And here it was... Ainz somewhat understood. "You reset Solution's level to one and used that World Item to bind another World Item to her as a passive skill, didn't you?" Now he was just resigned. That was positively genius, yet, so wasteful Ainz wanted to cry.
"It wasn't as easy. Normally, it was impossible to do that. Bless Tabula's luck and the idiot developer who allowed for such a blatant loophole." Rei snickered, "Basically, in the process of binding, you just had to swap the item for the World Item and it surprisingly accepted it. That's how Tabula found a way to make a World Item into a core for Rubedo. It was a simple fortunately unfortunate missclick during a panic."
Ainz facepalmed while groaning as if he just heard something mentally painful. Of course, there would be a buggy exploit like that. Yggdrasil was full of them if one bothered to look.
Ainz suddenly froze as a thought occurred to him, his skull snapping in Rei's direction, "How many?"
"How many what?" Rei tilted his head in confusion.
"How many World Items did you bind to her?" Ainz asked in alarm. As much as he wanted to believe the bastard in front of him wouldn't... he knew he would. He totally would exploit the shit out of this discovery!
"Ah..." Rei mournfully shook his head, "I tried to find a way but in the end, the [Potential to Reach the Heavens] can only be used once."
'Thank God, that almost made me grow a new heart out of fright...' Ainz inwardly sighed in relief. One World Item turned passive skill was bad enough. He didn't need an NPC having an entire repertoire of them walking around. "I guess you used it on yourself too, right? Now that you mentioned it, I vaguely remember you reset your level just a month after Rubedo was made."
"Yeah, I didn't bind a World Item to myself though. Would be a waste with my race." Rei said, "Here, let me show you..."
Suddenly, Ainz got the vague impression of Message skill connecting to him before a flood of information appeared in his head. For a second, he marveled at the ingenious use of the Message spell before he looked at what the information package contained.
It was... simply information about a passive spell Rei possessed. Raising his nonexistent eyebrow, Ainz looked at Rei, "You found a way to ping items and skill without interface." He deadpanned, inwardly impressed. Seeing that Rei just absentmindedly nodded, too preoccupied with the busty blonde snuggly cuddling into his chest, Ainz looked at the skill and momentarily froze.
[Last Man Casting]
He remembered that item. It was incredibly useful for the undead since the item converted stamina, normally useless hidden stat, into MP. Sadly, it was one-time use and quite hard to stockpile after developers saw undead races exploit it to get free MP bar refills.
The skill Rei acquired with his method was... just ugh. He could basically use his stamina to refill his mana exactly like the item could, except, there was no cooldown since the item was one-time use but the skill wasn't. Ainz got a vague feeling of headache behind his eye-sockets when he realized the most important fact.
Rei was an Incubus and had a racial trait called Infinite Stamina.
"You damn cheater, you have infinite mana." Ainz realized, rubbing the temples of his skull with his bony fingers.
Rei grinned. No, he didn't. The skill didn't work the way Ainz imagined. It wasn't nearly as overpowered but it was still game... and reality breaking in its own way. There was no real need to correct Ainz's assumptions though.
"Just tell me what World Item you used for Solution and let's call it a day. I don't think my mental state could withstand more mind-shattering revelations today." Ainz wearily said.
"Sure..." Rei casually shrugged, inwardly laughing his ass off as he nudged Solution who with a nod send the information about the passive skill to Ainz. After that, Rei just expectantly watched as the skeleton's mind combusted.
At first, Ainz hummed... then froze as if he was a statue... then groaned... and then he smashed his forehead into the table.
"Ten years... all casters of Yggdrasil tried their best to find it for ten whole years... any you had it all along!?" Ainz hysterically screamed before his emotions were forcefully calmed down, causing him to blankly stare forward in silence.
[Minerva's Might]
It was the most coveted caster-oriented item in all of Yggdrasil since the developers revealed its existence. A World Item dedicated to casters. Nobody ever found it.
[Minerva's Might] provided a massive temporary buff to a caster upon use. Its real value, however, came from the fact it was not one-time use but had a cooldown before the buff could be applied again.
Apparently, binding the effects of the item didn't give Solution the skill to apply that buff. No... it straight out gave her passive skill that provided the buff permanently, making her the most broken caster Ainz ever saw.
For example, the first effect of the buff made her completely immune to mental magic. Even a World Item like [Downfall of the Castle and Country] wouldn't be able to brainwash her because the [Minerva's Might] was one of the best World Items in the game.
When he saw the second effect, Ainz understood how could Solution's spells be so strong. She had a permanent buff that doubled the effect of her spells. That was just cheating on a different level. So much so Ainz decided to forget he ever saw it.
The third effect was a fifty percent reduction of mana cost to all spells.
The fourth effect was the answer to Ainz's question. The buff gave Solution the ability of Silent Casting, meaning she could take Instant Casting in her build and have both of them.
The fifth and final effect, however, was what made Ainz's brain fry the most. It was friggin' permanently doubling her mana pool!
Obviously, the developers never intended the buff to be permanent. That's why the original [Minerva's Might] had a long cooldown. It was supposed to be a trump card that could change a caster into something akin to a mini raid boss that threw devastating spells left and right for the duration of the buff. Yet, his guildmate apparently found another way how to screw the system big time.
Honestly, now Ainz fully understood why Rei focused on unlocking more magic spell trees for Solution rather than buffing up one...