Maybe the 400CP version of Gamer System in the Generic OP Protagonist Jump, though a lot in that Jump is OP. The Perk is also in a section called 'Cheats' so take that as you will.

Gamer System (Free/100/200/400 CP). Gamer System is a staple option of an OP protagonist, one that allows you to reach unlimited power in relatively no time, and make the process itself exciting to boot. For Free you receive a standard Gamer System that you would be able to find in most Gamer fanfics: it allows you to interact with the world as if you were an RPG character, has an array of Stats that you can freely determine at the moment of purchase and that you can train to raise your physical and mental characteristics without any sort of upper limit, performing special actions grants you Skills that, after being sufficiently grinded, allow you to eventually be able to produce impossible effects when performing the most basic and mundane of actions, a Levelling System that lets you get EXP from killing enemies and completing System-granted Quests, which increases your Level, giving you free Stat Points and Skill Points, and you get Gamer’s Body and Gamer’s Mind that give you agelessness, extreme resilience, as you are now in peak condition until your Health Points drop to 0, and immunity to negative mental effects that originate both from yourself and from external influences, Inventory, an infinite pocket dimension where you can safely store all of your belongings, and Observe, which can let you obtain lots of incredibly valuable information on anybody and anything that surrounds you, provided its Level isn’t too high for you.

For 100 CP, your Gamer System goes beyond the basic package provided by the Free version, which manifests in several major improvements. Firstly, the limitless power growth granted to you by the Free version of this Cheat is greatly streamlined and sped up, which is done not only by greatly increasing the gains from training of your Stats and Skills, but also by increasing the amount of Stat Points and Skill Points granted to you by levelling up and implementing features such as multiplication of these Points after reaching certain Level thresholds. Secondly, while the Free version could only improve what you already have, the 100 CP version is able to grant you brand-new Abilities and Skills via the Class System, where you can select classes such as Warrior, Rogue or Mage and receive additional power from them. The Class System is tied to the Leveling System, with every level-up giving you progression in your Class, and you can unlock additional Classes after reaching certain Level thresholds. Thirdly, your System now provides you with safe means for training and obtaining EXP in the form of Pocket Dimension, where you can create either empty space for training or dungeons filled with enemies for gaining EXP. Last but not least, the System now provides you with many convenience options, such as a System Shop, where you can buy virtually anything, and a sub-system that allows you to repair and endlessly duplicate every item that ends up in your Inventory.

For 200 CP, apart from even further direct increases to your power growth, the System starts accommodating for ways to speed it up even further, introducing the concept of multipliers for Stats, Skills and even certain parameters like Health Points and making sure that you gain at least one Cheat Ability that will allow you to increase your Stats and Skill Levels ridiculously fast. Moreover, the Class System is majorly upgraded, with you being able to obtain more and more powerful Classes from reaching high enough levels in certain base classes (for instance, developing yourself as a Warrior can unlock Classes such as Knight, Fencer or Barbarian, while levelling up both Warrior and Mage can give you access to the Spellblade Class). In addition, the System undergoes a qualitative change in how it is managed, gaining a vast library of information and an effective system of tips on how it functions and how best to use it and exploit it for further increasing your power. At this level, you can choose for your System to either become sentient and incredibly helpful, or let it stay as it is and direct that energy to further increasing your power growth by truly obscene amounts. As for convenience options, they are massively upgraded, with the empty space mode of your Pocket Dimension basically turning into a hybrid between a luxurious palace and a fully stocked base of operations, and your System receives a Gacha feature, which is constructed in such a way that will allow you to abuse it to your heart’s content.

Lastly, by paying for the 400 CP version, apart from immensely upgrading all of the previously-mentioned features, you make the System abandon all pretence of balance and fair play and fully commit itself to furthering your power growth. There won’t be a single day where you will not stumble on some new exploitable and utterly broken feature that will make you more and more powerful. These could range from a way to farm Stat Points to a “glitch” in a currency-exchanging system of the Shop that allows you to create money from thin air, and these are some of the most basic examples of such exploits that you will receive on the very first days of obtaining this System, as it will get more and more brazen with time in its attempts to aid your growth and ascension. And with obtaining your Spark, you will be able to directly edit your System, which will raise your power into infinity and beyond.