The Cat was created as a result of too many errors, and was immediately used to seal the Scream because that is important, in addition to being fused with The Weapon and the last reincarnation of the Axis Being. He was originally an Exploratory Force unit and citizen for the now-mostly-defunct SLYNERF League, and due to his properties of existence, survived the annihilation from Or Something Like That being sent to DINNER, alongside Jenna, King Harkinian, a number of other foreign entities, potentially some other Exploratory Force units, and Yard Zero. He is under the command of Nedben Prime, and is not to be trifled with due to the danger that he may break down entirely and become nonfunctional, releasing the entity inside. He is very easily enslaved in the standard methods of cat caretaking or invoking his name in a specific manner, though very few people outside of the League are aware of this. He is a kyneatmorashor-chesire black cat mix, though this pedigree is nonspecific and he has several other less defined heritages. As of one noodle incident he is now a prince of the Cloud Kingdom, though he has no intent of actually taking over and has only used this title to bash through legal issues in other countries under the pretext of invasion. His greatest fear is something that is not even comprehensible to mortals, and whenever invoked is disguised as an extremely eldritch screaming dog-like entity should it be seen by anyone else or actually generated to some extent for the sake of not destroying reality. He now works for Iael after the effective disbanding of SLYNERF.
As an Artificer (full title Artificer Technomagi Narrator, Creative Offices Grandmaster Engineer, Legendary Lord of the State of the Art), he possesses immense creation, modification, analysis, and destruction skills, along with decent magical capabilities, flight without explanation, narrative powers, engineering and other technological skills, and omnidisciplinary scientific knowledge from extremely esoteric compendiums and random sources. Due to a constant use of his power being to seal the Scream, he only displays a fraction of those skills unless actually using them would be helpful or he is requested/ordered to do so. He also blatantly displays the ability to listen to conceptual boundaries and to a limited extent call on those who manipulate them, allowing him to use teleportation gaps and store massive amounts of material in gap spaces.
As a magic cat, he posesses the power to willfully change between a cat and a catboy, though he prefers the latter for operation and the former for fleeing and subservience. More uniquely, he is an aspect of error and what has been destroyed, applying the power of that with ease, allowing him to use the skills of the dead and destroyed, as well as counteract and survive errors in reality such as time paradoxes, pime taradoxes, loops, and anomalies. The former portion of those powers is more often used than referred to, and using the skills of the deceased generally ends up being referred to more often than used. Counteracting errors in reality has almost never come up, though he does refer to gaining slight power from typographical errors.
As a fully dosed hourai immortal, he is immune to diseases and aging and heals even lethal and maiming injuries quickly without issue or disfigurement, along with respawning when destroyed through the power of eternity and an extremely powerful force against permanent non-preferable alteration along with negative alterations in general. This is actually only for durability, as Liebschen is not specifically much stronger than the average catboy otherwise and his death would cause problems. Since very few people actually are intent on killing him, he does not actually need to display this power very often. Yes, he is a masochist. Please don't leave dozens of cheap comments about this again.
His tools are an enhanced mini-hakkero reactor that contains a compressed quantum tower for use in material generation, the allweapon dagger Tchaikovsky, several generic knives, an original copy of the Esotericanomicon, the Logicannon Queen, green gaps, an unusually large amount of supplies stored in said gaps, and a few miscellaneous tools. Almost all of this is constantly dedicated to holding down the scream, so normally only Tchaikovsky, the knives, gaps, and a few elemental quanta are used, with the Logicannon Queen brought in only for emergencies due to a substantial lack of logic, physics, and sanity due to the priority of holding down the Scream.
As a friend of Iael, he can call on her powers of deadly music and stabby teleporting vines.
The Scream is an extremely powerful and eldritch entity, and a considerably stronger aspect of error and destruction than Liebschen, and displays all of his powers and much more. He tends to act through the Screaming Hounds that are Liebschen's greatest fear, and his personal physical form appears as a less than stable cloud of energies that attempts to destroy everything in error. The Scream has been known to destroy entire realities without effort and deploy legions of madgods and the Screaming Hounds en masse whenever unsealed for even a moment with Liebschen being held down and constantly killed enough, though the amount of destruction required to keep Liebschen dead long enough would usually leave very little to destroy.