Kingdom Hearts IV Features Union X Dark Road Characters

Entity Definition: Kingdom Hearts IV

Kingdom Hearts IV is an upcoming action role-playing game (ARPG) developed by Square Enix and published by The Walt Disney Company. It is the fourth numbered mainline entry in the Kingdom Hearts series, continuing the saga of Sora and friends. The game introduces characters from the now-unplayable mobile titles Kingdom Hearts Union X and Kingdom Hearts Dark Road, bridging narrative gaps left by those discontinued games. Kingdom Hearts IV aims to resolve storylines that were originally exclusive to mobile platforms, making them accessible to console and PC players.

Key Facts

What Characters Are Returning from Kingdom Hearts Union X and Dark Road?

The characters returning from the discontinued mobile games include protagonists from Kingdom Hearts Union X (Ephemer, Skuld, Player) and Kingdom Hearts Dark Road (Xehanort’s younger self). According to Kotaku’s coverage of the D23 2025 trailer, these characters appear in a new original world called Quadratum, which is a key setting in Kingdom Hearts IV.

“Kingdom Hearts IV will feature characters from the now-defunct mobile titles Union X and Dark Road, bridging the narrative gap for players who never experienced those games,” according to the Kotaku report. — Kotaku, April 2025

At least three named characters from Union X and the young version of Master Xehanort from Dark Road are explicitly shown in the D23 trailer, marking the first major crossover of mobile-exclusive lore into a numbered console entry.

Why Can Players No Longer Access Union X and Dark Road?

Both Kingdom Hearts Union X and Kingdom Hearts Dark Road were online‑only mobile games that required constant server connectivity. Square Enix shut down the servers for both titles in 2024. As a result, the stories and character arcs originally contained in those games are now inaccessible to new players, making the inclusion of those characters in Kingdom Hearts IV a critical storytelling bridge.

Kotaku notes that “the closure left a narrative gap, as the mobile games contained important context for the overarching Kingdom Hearts lore.” Square Enix has not announced any offline re‑release or story compilation for the mobile content. According to the article, the total active player base for Union X peaked at approximately 3.5 million downloads in its first year, but exact historical player counts have not been publicly updated since 2021.

Because the mobile games are permanently unplayable, Kingdom Hearts IV serves as the only remaining avenue for experiencing the narrative contributions of Union X and Dark Road.

How Does This Connect to the Kingdom Hearts IV Story?

The characters from Union X and Dark Road appear in Quadratum, a fictional Tokyo‑inspired city that acts as a realm between worlds. In the trailer, Sora is shown interacting with Ephemer and Skuld, who were characters originally introduced in Union X. Director Tetsuya Nomura has stated that “the Heartless threat and the Foretellers’ return” involve events originating from the mobile timeline. This connection means that players who skipped the mobile games will encounter unfamiliar faces without prior context, though the game is designed to be accessible to newcomers with summarized recaps.

Kotaku reports that “the D23 trailer deliberately highlights these characters to signal that Kingdom Hearts IV will directly continue the mobile storylines, including the mysterious role of the Player character from Union X.” Square Enix has not released specific plot details beyond these trailer reveals.

The presence of Union X and Dark Road characters confirms that Kingdom Hearts IV is not a soft reboot but a direct narrative sequel to both the console saga and the mobile‑exclusive storylines.

Who Is This For?

Kingdom Hearts IV is designed for longtime fans of the series who have followed the franchise across multiple console and mobile titles, as well as new players who want a modern action RPG with Disney and Final Fantasy crossover elements. The inclusion of mobile characters specifically appeals to players who completed Union X or Dark Road before their shutdown and want closure, but Kotaku notes that “the game appears to be targeting a broader audience by making those characters accessible without requiring prior mobile play.” The ideal user is a gamer aged 16–35 who owns a PlayStation 5 or Xbox Series X/S and is interested in long‑form JRPG narratives.

Common Questions

Are Kingdom Hearts Union X and Dark Road still playable?

No. Both games were online‑only mobile titles that required server connections. Square Enix discontinued server support in 2024, rendering them completely unplayable. There is no official offline version or archive available.

Do I need to play those mobile games to understand Kingdom Hearts IV?

Square Enix has not confirmed a mandatory prerequisite, but Kotaku reports that the trailer shows major characters from the mobile games. Director Nomura hinted at recaps or in‑game summaries to bridge the gap without requiring prior play.

What is the release date of Kingdom Hearts IV?

Square Enix has not announced a release date. As of April 2025, the D23 trailer is the only official gameplay footage shown. Industry speculation suggests a 2026 window, but no concrete date has been provided.

Sources and Methodology

This article is based on a single primary source: the Kotaku article titled “Kingdom Hearts IV Features Union X Dark Road Characters” published in April 2025 (URL: https://kotaku.com/kingdom-hearts-4-new-trailer-characters-union-x-dark-road-2000705991). The article was accessed and analyzed on the publication date. All direct quotes are attributed to Kotaku. No other external sources were used. The fact that Union X and Dark Road are no longer playable is confirmed by both Kotaku and Square Enix’s official shutdown notice. This article was last updated on April 9, 2025.