Chi-You  is an immortal playing a game for control of the Earth located in the dimension occupied by the Teenage Mutant Ninja Turtles.
Teenage Mutant Ninja TurtlesEdit
Chi-You is one of the powerful immortals who once ruled the Earth thousands of years ago. He is the brother of Kitsune and the Rat King. At some point, they mysteriously disappeared and inspired myth and legend. Ultimately, they fell from memory and man began to question if they ever really existed at all. The immortals agreed to a game to see who could regain control of Earth. Rules were drafted and only mortals could be used as their pawns. In Chinese legend and history, Chi-You was worshiped as a war god who led the Nine Li Tribe and fought Emperor Huangdi in the Battle of Zhuolu. 
At some point in the Muromachi Period (1337-1573), Chi-You sensed the power of Krang's Interspatial Teleportation Unit and journeyed across the sea to Japan to investigate if Kitsune was cheating or not. At first, he masked himself from sight but Kitsune sensed his presence and called out to him. Once Krang stepped from the teleporter's portal, Chi-You accused Kitsune of conspiring with a demon. He declared the act forfeits her from the game and he moved to take her soul. Kitsune dodged his attacks and tossed him into the portal. Due to safeguards in the teleportation unit, Chi-You was stranded in a state of eternal limbo. 
After an accident during testing of their own Interspatial Teleportation Unit, the Teenage Mutant Ninja Turtles, April O'Neil and Casey Jones were transported from their dimension to the dimension occupied by the Ghostbusters. They arrived in the Emmanuel Baptist Church during a wedding ceremony. Chi-You was freed as a result of the accident but manifested in an ethereal form with new powers. Ready to exact revenge on Kitsune, Chi-You was surprised to be unable to detect her or any of his brethren. The Turtles felt honor-bound to deal with Chi-You and attacked but they went right through him. Chi-You suspected they were demons sent by Kitsune to recapture him and retaliated. After blasting several wedding guests and Casey, Chi-You learned he could now control mortals like puppets. With their bodies and mind his, Chi-You began speaking in English and learned who the Turtles really were. He warned them not to interfere in his plans to take over this world.
The Ghostbusters were called by Janine Melnitz and Kylie Griffin after they finished a case. According to the team's Dimensional Inverter, there was a potential Class 7 on the East Side. The Ghostbusters made their way to the Emmanuel Baptist Church but were locked out. They improvised and made their own entrance. After experiencing the effects of the Proton Streams, Chi-You realized the Ghostbusters had the capability of capturing him. He ordered his minions to retreat and teleported out of the church. Egon Spengler thought it was strange both the Turtles were left behind and P.K.E. levels were declining. Winston Zeddemore called for a cease fire and both sides conferred. After April mentioned Chi-You, Ray Stantz recognized the name. Egon detected an emission of a low-level phase variance at the cellular level from the Turtles and April, which in part matched readings he took from Chi-You. A short distance from the church, Chi-You gathered his thoughts on a building rooftop. He concluded his family's pact to influence the world indirectly was null and void since he could not sense them nor any like them. He decided he would directly impose order and make the world as it should be. Once he conquered Earth, Chi-You would force the Turtles to build a teleportation unit that would give him access to other worlds he could conquer. Chi-You planned to achieve this with a proper army. Displeased with the wedding guests he took control of, Chi-You released his hold on them and declared his desire for worthy warriors but realized Casey was fighting his control. Chi-You hit Casey and ordered him to find similar warriors. Casey directed Chi-You to the Madison Square Garden.
Chi-You manifested in the Garden's hockey rink and disrupted Game 1 of the NHL Eastern Conference Quarterfinals. He grabbed players from both the New York Rangers and Montreal Canadiens and transmogrified them into proper warriors. Weakened by the ordeal, Chi-You was still satisfied with his new thralls. He sensed Casey's curiosity and admitted he didn't do the same to Casey. Chi-You planned to use Casey as an incentive to force the Turtles to swear allegiance to him and share their knowledge of traveling to other worlds.
Chi-You battled the Ghostbusters and Turtles once more but with the aid of his thralls. During the battle in the rink, Chi-You failed to notice Winston sneaking around the seating behind him. Winston opened a Trap but to everyone's surprise, Chi-You was not trapped. The direct connections he formed with his thralls was preventing him from being trapped.  Chi-You ordered Casey to free him. Casey got the jump on Winston, advised him to take out the thralls first, punched him and then released Chi-You. Chi-You vowed he would not be caught unaware a third time and teleported away. He took refuge in Chinatown. Hours later, while in the Mahayana Buddhist Temple, Chi-You realized Casey was purposely fighting his control and using their mental link to weaken him. Chi-You was infuriated and swallowed Casey whole. Chi-You enveloped Casey inside an adaptable ectoplasmic casing that allowed for finely tuned manipulation of the corporeal form. 
Chi-You transformed into a new form, that of giant humanoid bull, and stormed Chinatown. After the Ghostbusters received a call from the Tai Hong Lau Restaurant, they split up. Peter, Winston, Leonardo, Michelangelo, and Raphael went after Chi-You. Once Chi-You witnessed Michelangelo liberating one of his thralls, he ordered the rest of his army to retreat. At Peter's behest, Chi-You stomped the ground and knocked Peter and Winston back. He threw up Casey, who was drenched in ectoplasm. Casey stood up in a transmogrified form. Back in his regular form, Chi-You focused on Casey and manipulated him like a puppeteer to his puppet. Since none of the three Turtles were skilled enough to help him with building a teleporter, Chi-You ordered their deaths. Peter took advantage of the situation and got out the Proton Bazooka. He took aim and blew Chi-You up, dispersing his spectral form. Raphael zapped the distracted Casey and restored him to normal. The Ghostbusters and Turtles returned to the Firehouse to sort things out. Leonardo was insistent he and his brothers would help the Ghostbusters fight Chi-You until the last possible moment then teleport home. While work on the teleportation unit and an electromagnetic pulse emitter progressed at the Firehouse, Chi-You reformed in Chinatown. Not pleased with defeat, Chi-You concluded he couldn't ignore the Ghostbusters and Turtles any longer. He shifted his focus to hunting and destroying them.
Chi-You had his thralls force their way through the entrance into the Firehouse and draw most of the Ghostbusters and Turtles into a firefight. Meanwhile, he teleported to the second floor R&D laboratory and prevented Ray, April, and Kylie from activating their Electromagnetic Pulse Emitter. Before Chi-You could kill them, Casey triggered the pulse. Chi-You changed his mind and decided he would enthrall them and make them kill each other. He discovered the pulse negated his ability to entrall. Chi-You soon settled with peeling the flesh off Ray but Winston and Peter intervened. Leonardo threw out a Trap and attempted to capture him but Chi-You yanked Winston's Proton Stream. The Trap was closed as Winston was pulled forward. Everyone discovered Chi-You had possessed Winston. Chi-You declared his warrior's body was worthy of a conqueror. Ray tried to douse Chi-You in positively charged Psychomagnotheric Slime from the Miniature Slime Blower but he ducked at the last second. Chi-You knocked Ray unconscious then transmogrified his host body into a bull form.
Chi-You charged through the wall and continued fighting Leonardo and Raphael in the main section of the second floor. They were no match for him. As Chi-You declared he would grind them into Guilianggao, Michelangelo got into position and blasted him with a Slime Blower. Winston was not completely exorcised and struggled with Chi-You for control of his body. Raphael easily diverted Chi-You's attention while Leonardo shocked Winston with his pack attachment. Peter trapped Chi-You on cue. After the Turtles, Casey and April took the Interdimensional portal back to their home dimension, Peter opened the floor up to whoever wanted to place Chi-You into the Containment Unit. Winston understandably didn't want Chi-You anywhere near him and had Egon change the teleportation unit's point of destination to Proxima Centauri in the Turtles' dimension. Winston tossed the Trap through. Even trapped and 4.2 light years away from Earth, Chi-You could sense the presence of his family again. He vowed to find his way back to them, eventually.
Chi-You bears the traits of a bull and can transform into one.
Chi-You has the power of immortality and transformation. He is also adept in martial arts. In his ethereal form, Chi-You can be intangible, directly and remotely possess humans, can transmogrify host body and any equipment worn such as a Proton Pack, extend his arms, teleport, can gift his power to humans and transmogrify them to enthrall them to his will, and telekinesis. He used a form of telekinesis to remotely detonate a cell phone. In addition to controlling a host's body, he also controls their mind and can add their knowledge to his. In the process of bonding to his thralls, Chi-You forms tethers to each one. As a result of this direct connection, Chi-You can't be trapped. Each connection must be severed first. To exact further control of a remotely possessed human, Chi-You can swallow him or her whole. Enveloped inside an adaptable ectoplasmic casing, he can finely tune the manipulation of the corporeal form and even transmogrify the human. Once the human is thrown up, Chi-You can manipulate them with psychokinetic gestures much like a puppeteer manipulating a puppet.
In terms of weaknesses, Chi-You's short temper often leads to poor decision making. Chi-You's mental link with possessed humans isn't absolute. Casey demonstrated the will to fight his control. After transmogrifying many humans at a time, Chi-You weakened a deal.
- Tom Waltz suggested using Chi-You in an early proposal for the Teenage Mutant Ninja Turtles/Ghostbusters mini-series. 
- Chi-You is based on Chi-You, the god of war from Chinese mythology.
- Chi-You is a strict adherent of rules. 
- On page 12 of TMNT/Ghostbusters Issue #3, Peter calls Chi-You "Ferdinand" after the character from the "The Story of Ferdinand" book and his comments on Chinatown appear to be an allusion to Jazz duo Slim & Slam's songs "Chinatown, My Chinatown" and "Ferdinand the Bull"
- On page 18 of Ghostbusters: Get Real Issue #1, on the white board, in the middle, is a photo of Chi-You.
- On page 11 of Ghostbusters: Get Real Issue #3, the photo of Chi-You appears in the middle of the white board.
- Teenage Mutant Ninja Turtles Ghostbusters
- Ghostbusters Annual 2015
- Alluded to in the Story So Far page. 
- ↑ Kitsune (2014). IDW Comics- "Teenage Mutant Ninja Turtles/Ghostbusters Issue #1" (2014) (Comic p.4). Kitsune says: "Temper, temper, Chi-You."
- ↑ Ray Stantz (2014). IDW Comics- "Teenage Mutant Ninja Turtles/Ghostbusters Issue #2" (2014) (Comic p.5). Ray says: "He was a war god, right? Led the Nine Li Tribe and fought the Battle of Zhuolu against the Emperor Huangdi?"
- ↑ Krang (2014). IDW Comics- "Teenage Mutant Ninja Turtles/Ghostbusters Issue #1" (2014) (Comic p.5). Krang says: "There are safeguards on this portal to prevent unwanted incursion. He won't be able to enter my world... nor will be able to simply turn back. At best he has been destroyed. At worst, irretrievably lost and aware of every second. A hellish, eternal limbo."
- ↑ Ray Stantz (2014). IDW Comics- "Teenage Mutant Ninja Turtles/Ghostbusters Issue #3" (2014) (Comic p.5). Ray says: "He should've been sucked right into the trap. There's no way he could fight it unless--unless he's more directly connected to his thralls than we thought."
- ↑ Ghostbusters Wiki Interview with Erik Burnham Part 3, Question 3 answer 12/14/15
- ↑ Kylie Griffin (2014). IDW Comics- "Teenage Mutant Ninja Turtles/Ghostbusters Issue #1" (2014) (Comic p.13). Kylie says: "Tell the guys I can confirm a potential Class-Seven on the East Side."
- ↑ Peter Venkman (2015). IDW Comics- "Teenage Mutant Ninja Turtles/Ghostbusters Issue #4" (2015) (Comic p.5). Peter says: "We're gonna get you a souvenir for all this - "I fought the minions of an uppity Class 7 and all I got was this lousy T-Shirt.""
- ↑ Peter Venkman (2015). IDW Comics- "Teenage Mutant Ninja Turtles/Ghostbusters Issue #4" (2015) (Comic p.5). Peter says: "Godlike being."
- ↑ Tom Waltz (2015). IDW Comics- "Teenage Mutant Ninja Turtles/Ghostbusters Director's Cut" (2015) (Comic p.10). Tom says: "I learned about Chi-You online after doing some research and suggested him as the crossover's baddie in an early proposal I put together and both Bobby and Erik were in agreement we go with him."
- ↑ Kitsune (2014). IDW Comics- "Teenage Mutant Ninja Turtles/Ghostbusters Issue #1" (2014) (Comic p.3). Kitsune says: "Oh, my dear brother, it's been so long, I'd almost forgotten how much of a slave you can be to your little rules."
- ↑ Narrator (2015). IDW Comics- "Ghostbusters Annual 2015" (2015) (Comic's Story So Far). Narrator says: "They fought alongside mutant ninjas against a spectral Chinese warrior."