Wallace "Ace" West is a superhero appearing in American comic books published by DC Comics. He was originally introduced as a biracial interpretation of Wally West as part of DC's The New 52 relaunch. The comic DC Rebirth #1 later established that he is a new character of the same name, being a Reverse-Flash's (Daniel West) son and Wally's cousin, both named after their great-grandfather.^[1] To avoid confusion, the character was renamed in later comics as Wallace West, and later simply as Ace West.

The character was inspired by a desire to feature an African-American iteration of Wally West in the Arrowverse series The Flash following the similarly black Jesse L. Martin's and Candice Patton's respective castings as Joe and Iris West. Ultimately, Keiynan Lonsdale was cast as the character, depicted as West's long-lost brother. Lonsdale reprised the role in Legends of Tomorrow and Supergirl.

The "reintroduction" of this character to DC Comics following its 2011 The New 52 reboot, which removed Wally West from continuity, was first announced in January 2014.^[2] Originally conceived of as a biracial reinterpretation of the classic Wally West character. Wallace/Ace is stated in his introductory comics and creators as being the son of Iris West's brother Rudy, as in pre-New 52 stories.^[3][4][5] However, the original interpretation of Wally West, having been the starring character in the Flash for many years, was still missed by DC's fans, and so the company decided to bring the original Wally back into continuity in Geoff Johns' DC Rebirth #1 (2016). Rebirth retroactively established that the character's father was not Rudy, as previously stated; he was the son of Iris's other brother, the then-recently introduced Daniel West, also the latest incarnation of Reverse Flash, who had redeemed and sacrificed himself as a member of the Suicide Squad. Following his cousin's reintroduction, the character was depicted as going by their full name "Wallace", and later a new nickname, "Ace".

Wallace "Ace" West (then-referred to as simply "Wally") first appears in The Flash (vol. 4) Annual #3 (June 2014) in a story set twenty years in the future, when a jaded, older Flash (Barry Allen) reads about the character's funeral and vows to change history.^[6] Tying in with the ongoing story The New 52: Futures End, the story The Flash: Futures End #1 depicts an encounter between Barry of five years in the future (when Wallace is supposed to die) and the Barry of 20 years in the future, who is out to prevent it. In the course of the story, Wallace ends up learning that Barry is the Flash and absorbs part of the Speed Force — the source of the Flash's abilities — during the battle between Barry and his future counterpart. He becomes a speedster but his hero career is short-lived; he sacrifices himself to fix a wound in the speed force. Due to the effects of time travel, however, this has implications for Wallace earlier in his history. Around the same time, in the present-day narrative of The Flash, Barry meets Wallace for the first time through Iris. He is struck by lightning and acquires super-speed abilities; an apparition of his future explains that, as a consequence of how his future-self had died repairing the Speed Force, all the power within him was able to travel back in time and use Wallace's lightning accident as a catalyst. Wallace's first act as a speedster is to use his powers to protect a classmate from a bully, using the same artistic elements as Professor Zoom's powers.^[7]

DC Rebirth #1, part of a company-wide event of the same name, marked DC's attempts to restore much of what it lost in the New 52 reboot, both in tone and in the stories of its characters. It features Wally West watching his younger cousin, Wallace, from outside of time, proud and amazed that he too has become a speedster, and reflecting on how they are both named for the same grandfather. Wally is brought back to reality by Barry, who remembers him for the first time since the events of Flashpoint. Teen Titans Rebirth #1, shows Wallace joining the Teen Titans superhero team as Kid Flash.^[8]

Wallace, as Kid Flash, meets Wally West, as the Flash, when assisting Barry in dealing with a bridge accident, although Wally doesn't explicitly introduce himself to his cousin, simply identifying himself as an ally of Barry, although Wallace accepts him after they work together to save Barry from a temporary infusion of Speed Force energy.

He later discovers that he has been created after Barry created Flashpoint timeline, abandoning his "Wally" nickname in favour of going by his full name of "Wallace", before ultimately going by the new short-hand nickname of "Ace" West.

In "The New Golden Age", Ace is among those who attend a party held by the Flash family.^[9]

Ace possesses super-speed and other abilities that are wielded by the Flash family.