Sticks the Badger vs. Duskmon (Koichi Kimura) (from Digimon Frontier, and Sonic Boom, Sonic the Hedgehog series)
Marshadow looks similar to Chao (species) (from Pokemon, and Sonic the Hedgehog series)
Sonic the Hedgehog series: The reason why Shadow the Ultimate Lifeform doesn't know or recognized Infinite (former Jackal Squad leader; the Ultimate Mercenary) in Sonic Forces, because he put his own past behind him and pretended it never happened. Shadow doesn't care.
(Part 1) For future Sonic the Hedgehog series: Imagine if... Infinite (former Jackal Squad leader; the Ultimate Mercenary) discover of how Shadow the Ultimate Lifeform got awakened and released by Rouge the Bat in Sonic Heroes for some reason?
Imagine if... Shadow the Ultimate Lifeform and E-123 Omega had a different story in a alternate timeline or universe? (Meaning: What should've happened)
Similar to Mega Man Zero, Megaman ZX, Azure Striker Gunvolt, and Gunvolt Chronicles: Luminous Avenger iX.
(Part 2) Sonic the Hedgehog series: End of Shadow the Ultimate Lifeform vs. a mysterious human girl
Mysterious Girl: (feeling weak) I never wanted this for you. I never wanted any of this for you...
Shadow: (steps back and tries to attack her again)
(Part 1) Sonic the Hedgehog series: End of Shadow the Ultimate Lifeform vs. a mysterious human girl
Shadow: (finally defeated and killed a mysterious huan girl)
(Part 3) Sonic the Hedgehog series: Shadow the Ultimate Lifeform vs. a mysterious human girl
Rouge the Bat: Argh!
Shadow: (sees Rouge got hurt and looks at a mysterious human girl)
(Part 2) Sonic the Hedgehog series: Shadow the Ultimate Lifeform vs. a mysterious human girl
Rouge the Bat: (to Mysterious Girl) He belongs to me, handsome.
Mysterious Girl: (to Rouge) I will not allow you to corrupt him further!
For future Sonic the Hedgehog series: Imagine if... Shadow the Ultimate Lifeform kill the ghost spirit of Maria Robotnik?
Hint: Similar to Starkiller (Galen Marek) vs. the ghost spirit of his father (Kento Marek) from Star Wars: The Force Unleashed (Wii version)