(Capcom's primary storyline)
Eliseo Mabou (also known as Morio) is a character of BIOHAZARD Heavenly Island. He is the older brother of Marilou Mabou. The nickname "Morio" was given by Takeru Tominaga, which means "harpoon man (銛男, morio)" in Japanese and "monster, deformed person" in Latin.
The mutated Eliseo has a mask on his face, and is clad in a trench coat. He is equipped with a long harpoon and a big anchor attached to a thick chain.
The creature relentlessly chased Tominaga and Yuki Mayu, ultimately cornering them atop a cliff, forcing them to hide in a tree. Tominaga fought the creature to save Mayu and they both fell over the edge of the cliff, with Tominaga using a rope tied around his waist to pull himself up. However, the creature used its anchor to pull itself up as well. Tominaga caused the creature to fall into the ocean below by kicking the anchor loose and it was presumed dead until the duo later encountered it within a tribal cave settlement.
The creature chased Takeru and Mayu again but this time it was confronted by the arriving BSAA soldiers led by Parker Luciani, and also by an unknown creature named Schraube Dämon, who assaulted Inéz Diaco and Marilou earlier and killed Mike D. Seaman. The fight ensued and Schraube Dämon was defeated. After the survivors encountered Dr. Dirk Miller, he explained that both creatures were natives of the island chosen for a project Miller called Kodoku Project which was based on the Survival of the Fittest ideology. Morio emerged as the strongest after again fighting Schraube Dämon and killing it, and it was speculated by Miller that he was, in fact, Marilou's missing brother and that Schraube Dämon was once López, a man who had competed for her affection but was stopped by her brother after acting aggressively towards Marilou. After seemingly dying at Zǐlì's hands, Morio emerged once again, and during a battle with monstrous Zǐlì, she destroyed his mask revealing that he was indeed Eliseo. Holding onto his human memories, Morio decided to save his sister from the mutated Zǐlì, and as he fought the creature, Claire Redfield fired a rocket launcher decapitating Zǐlì with Morio seemingly perishing in the explosion.