Robert Downey Jr. as Tony Stark/Iron Man. Armored Avenger and Leader of the Avengers, Robert Downey Jr needs to reprise his role as Iron Man after he must survive Avengers 3 and 4 so he can take on the real Mandarin(Byung Hun Lee) of the Ten Rings throught all of Phase 4 up to Avengers 5
Byung-hun Lee as Zhang Tong/Mandarin. Leader of the Ten Rings and the actual and proper marvel cinematic version of Iron Man's arch enemy from the comics. This version like the actor is to be Korean instead of Chinese so that actual MCU version of the Mandarin himself can adapt more flawlessly with some of the events that occurred in the 1980's where he stowed away on a ship from Shanghi to Peru where he under the request of Roselyn's father goes into the ruins of Macchu Picchu instead of a jungle to optain the ten magic powered rings and Quetzelcoatl taught him how to use each one of them before he started using them to save his wife and many innocent villagers from HYDRA's attack and after her father was murdered by the Winter Soldier and with Zhang as the Mandarin having used the power of the rings to help her father's cartel wipe out most of the soldiers that were attacking the village, sparing no one but 5 in which he and the surviving cartel militants interrogated and after learning that Zola during Operation Paperclip corrupted the world leaders into secretly rebuilding HYDRA, he and 3 the cartel executed 3 of the soldiers and the spy who betrayed Roselyn but only spares one in which he frees from HYDRA's control with the power of his rings, redeeming him and after helping Roselyn move pass her loss, he along with Quetzelcoatl as the original Mandarin before him trained her and many of the cartel militants every martial arts, self defense, and hand to hand combat skills that he knows so that they can defend themselves against anyone who threatens them before Zhang used the power of the rings to guide everyone safely from Macchu Picchu to Dublin, Ireland where they became official residents of the country. After that, Zhang Tong as the Mandarin will have orchastrated some of the real world events that involved making HYDRA lose military control over the world which led to the end of the Cold War as well as freeing the leaders of Russia, Romania and many others from HYDRA's influence as well as informing the North Korean prime minister about HYDRA being the reason why the Americans intervened with their campaign of reuniting their country with the south was just so they could play them for fools, and by learning that he and his army aren't alone, he leads the Romanian Revolution and frees both Romania, Russia and most of the World Country leaders from Zola's control. He even would be the one responsible for turning the other winter soldiers against the soviets which led to the entire russian military organization's collapse. His goal much like the character from the comics but at a lighter tone to ensure that Marvel will not screw up the actors portrayal as the MCU version of Tony Stark’s real arch enemy, Byung Hun Lee’s Mandarin is to make sure that all of the worst and most corrupt members of HYDRA are wiped out from the face of the Earth while sparing those who are smart and responsible enough to learn from their mistakes just like him. After Iron Man 4, the Mandarin is to also act as the main antagonist for Phase 4’s Avengers 5 by acting as Leader of the MCU’s Thunderbolts and Master’s of Evil with Helmut Zemo as the team’s second in command.
Italia Ricci as Bethany Cabe, a new agent of SHIELD who assists Tony in his mission on stoping the Mandarin and the Ten Rings in this 4th installment, also to make the character more interesting of a female lead for this film and its sequels is by having her in the MCU be portrayed as an Irish descendant of a banshee while capable of defending herself with Sonic Screams, self defense and martial arts combat moves which is to lead the character into helping Tony strengthen his physical reflexes and fighting techniques before his faceoff with the Mandarin. Ricci’s version of Bethany Cabe will be recommended to donning her own War Machine armor in the sequels to Iron Man 4.
Benedict Cumberbatch as Dr. Strange, as a man skilled in Magic and Physical Combat techniques as well as having started off as a man who lost his job caused by the accident that cost him his hands and later resisted giving into madness thanks to Kacillius acting as his opposite on the paths they choose over grief, Strange was able to maintain his mental stability after the moment he apoligized to Christine Palmer for being so hard on her but also because of the sling rings he and his fellow sorcerers use to quickly travel from one location to another remote location within seconds, his role as team extractor to getting Tony, Arno, Bethany, and Bucky onto the Mandarin’s Skycarrier whether it’s on the ground or in the air as well as getting them off the ship before something worse happens including to whatever links Wong and his fellow sorcerers to the Mandarin Zhang, his Family in Ireland, and his paramilitary organization the Ten Rings before HYDRA was exposed in the Winter Soldier film.
Mark Wahlberg as Arno Stark, Tony's wayward brother who in the MCU is the son of Howard Stark and a woman he once had an affair with back in the late 60s or early 70s who started his relationship with Bethany Cabe one night around 1992. He and Tony are to meet for the first time while Stark and Cabe are in the middle of their quest of investiga
Don Cheadle as James Rhodes/War Machine; Tony's best friend and colonel who will assist Tony, Cabe, Bucky and Arno in the climax against the Ten Rings and Hydra on the Mandarin's skycarrier ship
Oscar Issac as The Ghost, the Mandarin's second in command and elite assassin who in the MCU will also be the brother of the Mandarin's wife as well as Sasha's uncle who survived the raid on his father's drug compound.
Gwyneth Paltrow as Pepper Potts who in the end of the movie is to get her Rescue armor so she can help Tony and Rhodey in the future films.
Elizabeth Olsen as Scarlet Witch
Tom Holland as Spider-Man
Grey Damon as Kearson Dewitt; New CEO of AIM after Aldrich Killian who provides the Ten Rings and Mandarin with a helicarrier bigger than the all three Project Insight gunships to destroy HYDRA
Sebastian Stan as the Winter Soldier. Who will join Iron Man and his team to seek redemption for the murder of Tony's parents against the Mandarin, the Ten Rings and every HYDRA agent on board the sky carrier.
Morena Baccarin as Roselyn the Mandarin's wife who is saved by Zhang back when he became the Mandarin and remained by his side without being involved in any military conflict while moving forward with her life in Ireland with their daughter.
Selena Gomez as Sasha, the Mandarin's daughter
Samuel L. Jackson as Nick Fury
Benito Martinez to portray Quetzalcoatl; as the Marvel Cinematic version of the sun god in Central American folklore, Quetzalcoatl will be depicted as a makulanian dragon who served as the original Mandarin during the ancient times in the State of Mexico of Central America and later inspired many throughout the Middle Ages before he went deep into the ruins of Macchu Picchu for exile while guarding the rings until Zhang in the mid 80's obtained the rings and having proved himself worry. After training Zhang how to use the power of the rings through maintaining responsibility and optimism as well as teaching him his most highly skilled martial arts techniques, Quetzelcotal helped Zhang rescue his wife who was betrayed by her first fiance who was revealed to be a HYDRA agent after Zhang foresaw the situation with the rings power and subdued the mole from attempting to murder her with his gun by using telekinisis from the ring on his right middle finger to move the gun away from Roselyn while keeping him from pulling the trigger before Zhang as the new and current Mandarin after the Sun God incapacitates the mole with ice and brought Roselyn safely into Quetzalcoatl's chamber for sancuary before he went back to rescue other innocent villagers caught in the battle between HYDRA's Strike team and PDF and guided them safely through a portal he forged with the power of his ringsinto the secret chamber of Macchu Picchu where Quetzalcoatl kept them and Roselyn safe from harm, as Zhang as the Mandarin himself assisted her father's remaining drug cartel along with some of Manuel Noriaga's PDF into killing every American Strike team in the area while leaving a few and their mole alive as he and all remaining cartel militant and PDF's who betrayed HYDRA's puppets into Macchu Picchu where the Mandarin himself got them to confess that Arnim Zola corrupted many SHIELD and government officials into secretly rebuilding HYDRA during Operation Paperclip and how Bucky was still alive after Zhang subdued him from knowing about him as the Mandarin while using his mind control ring to to make sure he doesn't tell SHIELD or Alexander Pierce anything that he saw other than the drug lord he assassinated and after the Mandarin tortures the mole and captive HYDRA scumbags for destroying most of the village they attacked and for all the people they selfishly murdered, he and the remaining cartel grunts killed the corrupted US soldiers before they could say "Hail Hydra". After that, Quetzalcoatl told Zhang that after his days of being the Central American Sun God came to an end he then traveled the world and after a millennia of ruling and inspiring many cultures and people during the middle ages that he had been searching for someone worthy of wearing the ten power rings in possession, and after seeing Zhang use the rings not just to eliminate the enemy that invaded the town his wife's father ran and was killed in out of anger but to save those who in danger the dragon then entrusts Zhang with the rings as the next Mandarin who then reformed the Ten Rings cult as the paramilitary organization that is still at large on Earth in the Marvel Cinematic Universe. Later Doctor Strange frees Tony, his father and Trevor Slattery from captivity the Mandarin and his armies held them with a portal he opens to bring the three into Quetzalcoatl's secret den where the great dragon himself tells them everything about Zhang on how solid his reasons for being the Mandarin the armored Avenger is yet to deal with he is today and later after Tony, Arno, Rhodey, Bethanny and Bucky settle their skirmish with the Mandarin, Ghost, The Ten Rings operatives and the HYDRA soldiers onboard the huge helicarrier that the two rival organizations were battling eachother in as Zhang himself had the ships turrents destroy at least 14 major HYDRA bases scattered remotely in western Europe, Quetzalcoatl will help Iron Man destroy Ultimo in the final act fourth installment's epic climatic battle while stating that this would be the only time he would oppose his successor for his ideals and will be sure to return for the 5th Avengers movie in Phase 4 and the final Iron Man film.
Robert Davi as a South American Drug Lord who was the father of the Mandarin's wife who was assassinated by the Winter Soldier in the 80's while HYDRA was still in secret control of SHIELD
Now for some of the optional choices of characters that Marvel could include in Iron Man 4
Chris Evans as Steve Rogers/Captain America; the first avenger who Tony would send along with Scarlet Witch Pepper as Rescue and Spider-Man to protect Roselyn and Sasha from being assassinated by any HYDRA corrupted guards and after helping the Mandarin's family and most optimistic security guards subdue and free those under HYDRA's influence, he would inform Zhang that his family is safe, all guards that HYDRA corrupted are now free from their control which would lead to the films big twist where Zhang as the Mandarin has his Ten Rings Operatives reset the Sky Carrier's algaritham into lining up all HYDRA bases in all NATO alligned countries of Europe and has his Russian Ten Rings leiutenant openfire on all the troops and vehicles in their vicinity leaving only the colonels of those bases left standing so that HYDRA cannot respawn anymore troops starting from Scotland and to the borders of Russia and the countries that were formerly a part of it.
John Slattery and Dominic Cooper as Howard Stark
Guy Pearce as Aldrich Killian/Firebrand; the founder and former CEO of AIM who is resurrected by Zhang for Tony to understand that Killian was never the Mandarin and that his reasons for framing his organization was because he fired him for his serums being unstabled and then Zhang as the real Mandarin kills Killian with the disintegration ring for his madness after he bests the desperation driven maniac in a brief fight in his HQ in Hungary.
Another villain that maybe featured to the film that would regard the Mandarin's plot would be another one of Iron Man's biggest enemies;
Ultimo
In the comics, Ultimo was used by the Mandarin for one of his desired schemes against Iron Man but if you and imagine Ultimo being a large robotic weapon that the Mandarin's associates helped his organization built that would transform from and into a massive hellicarrier that is the size of the three from Captain America the Winter Soldier, you would all know where i am getting at
Cameos to include Stan Lee,
Now for the directors for Marvel to choose on replacing Shane Black on directing Iron Man 4 so that they can for goodness sake get the actual yet to be introduced version of the Mandarin done right with the power rings and the armor and with more appropriate and flawless backgrounds as a Korean Male instead of Chinese without screwing him up like they did with the two phonies in Iron Man and without making the problem worse/ They are;
Michael Bay - While Michael Bay remains reluctan
Antoine Fuqua
Alan Taylor
Steven Spielberg
James Cameron
George Lucas
Robert Zemeckis
Ron Howard
or the Russo Brothers since they are careful on respecting and handling characters in the films
For now while we wait, we should continue focusing our hopes on the outcomes of every film in Marvel Phase 3