The Watcher breaks his oath and recruits heroes from across the multiverse to battle against Ultron.
| Name | Type | Role | |
|---|---|---|---|
| A.C. Bradley | Writer | ||
| Cynthia Kaye McWilliams | Guest Star | Gamora | |
| Ross Marquand | Guest Star | Ultron | |
| Georges St-Pierre | Guest Star | Batroc | |
| Michael B. Jordan | Guest Star | Killmonger | |
| Toby Jones | Guest Star | Arnim Zola | |
| Chadwick Boseman | Guest Star | Star-Lord T'Challa | |
| Ozioma Akagha | Guest Star | Shuri | |
| Tom Hiddleston | Guest Star | Loki | |
| Brian T. Delaney | Guest Star | Peter Quill | |
| Chris Hemsworth | Guest Star | Thor | |
| Lake Bell | Guest Star | Natasha Romanoff / Black Widow | |
| Kurt Russell | Guest Star | Ego | |
| Mick Wingert | Guest Star | Tony Stark / Iron Man | |
| Benedict Cumberbatch | Guest Star | Doctor Strange / Strange-Supreme | |
| Frank Grillo | Guest Star | Brock Rumlow | |
| Bryan Andrews | Director |