Mipherius

Mipherius (ミフェリアス) is an non-canon character created for the That Time I Got Reincarnated as a Slime: Isekai Memories x KonoSuba collab.

Appearance
In his initial form, Mipherius takes the form of a knight in a suit of plate armor wielding a halberd. Instead of a face, he instead has a mass of purple smoke with glowing blue slits for eyes.

After being pushed into a corner, Mipherius uses his ability to assume a monstrous form that combines Charybdis and the Giant Toad from Konosuba, referred to simply as Charybdis Toad.

Personality
Mipherious is an individual filled with Envy; Envy for those who succeed where he has failed. He bears an irrational hatred for those who are "lucky", calling them "cheats" and plotting their downfall. He's the embodiment of a stereotypical sore loser, the type that shouts "Normies Explode" when they see a happy couple on the street.

Background
Mipherius was born from the collective resentment of various human Otherworlders who were "failures". Those who were reincarnated but died as infants, those who were summoned but died in the process, and so on. When he was born, he had gained two special abilities, those being "Interdimensional Travel" and "Concept Fusion". Using these two powers, he began to go universe to universe hunting down those that had succeeded where the souls that Mipherius was made of had failed.

Chronology
At some point, Mipherius came into conflict with Kazuma Satou and his party of adventurers. Being envious of his perceived "harem", Mipherius flew into a rage and attempted to kill them all. However, when faced with the 'Explosion' of Megumin, he found its power a bit too much to handle and opened up an interdimensional portal to contain the blast, unintentionally sucking Kazuma and his friends into the Central World in the process.

He would attempt to provoke Gabiru into all out fight with Kazuma but Rimuru quickly broke up the fight. Later on he would summon in Cabbages to attack Rimuru and Kazuma's party which ended up in failure.

Later on he would reveal himself and attempted to destroy them personally, but Rimuru used a barrier to stop him from phasing through their attacks, Out of desperation he transforms into Charybdis Toad and attempted to attack Tempest. With the effort of Rimuru and Megumin's combined explosion spell, Mipherius was finally ended once and for all.