Arknights is a free-to-play gacha game that blends tower defense with RPG elements to create a perfect mixture of challenging tactical gameplay with compelling world-building. It is well-loved globally, boasting a revenue of $248,110,000 in 2025 [1] and an impressive record of six years of live service while still going strong. One of the key factors for this relevancy is the creativity of its minigames that complement the main game. Alliance Protocol is its third successful implementation, where classic Arknights mechanics get a refresher within an auto chess context to excite loyal players and invite new and returning ones.
What is Stronghold Alliance Protocol?
Although tower defense is not new, Arknights’ tower defense system is unique in that each “operator” (character) acts as a tower with a distinct skill. Belonging to one of eight different classes, these operators can be deployed and redeployed after a cooldown period. The game gained immense popularity due to its challenging and multifaceted strategy. Meanwhile, auto chess is a strategic subgenre where the characters fight automatically on a chess-like board, and players can upgrade them between combat phases. Popularized by titles like Teamfight Tactics and Dota Underlords, it took the gaming community by storm, prompting many developers to create their own versions, and Arknights is no exception. Stronghold Alliance Protocol was therefore introduced as a time-limited event in Arknights on April 25th, 2026. This crossover is a natural fit, considering the Arknights audience already enjoys tactical, puzzle-like gameplay. The developers went above and beyond to create a unique auto-chess experience by seamlessly blending it with the game’s core tower defense mechanics, narrative, and world-building.
Auto Chess Meets Tower Defense, Reimagined
Both genres already feature deep layers of strategy, but Stronghold Alliance Protocol takes them to the next level. The mode combines the innate mechanics of auto chess, such as team synergies, buffs, and economy management via “funds” given each round, with the core elements of classic Arknights, including character positioning and skill synergies. On top of that, it introduces cooperative multiplayer layers that increase both the difficulty and the fun. This creates a trifecta of challenging strategies, making it highly replayable and rewarding for players, also encouraging people to team up with their friends to explore the gameplay together.
These layers offer a refreshing take for long-time Arknights fans, allowing them to explore the synergies of characters that are usually not considered “meta” while conquering a brand-new challenge. The team aspect also entices them to invite friends who might be new or returning after a hiatus. For newcomers, it serves as an exciting introduction to Arknights’ gameplay mechanics, paired with the addictive nature of auto chess. This invites them to play and replay until they master the mode, all without needing to dive heavily into the main game which can be overwhelming.
Narrative and Storytelling is the cherry on top!
The groups’ synergies and buffs in this game mode are entirely written based on the game’s lore, showcasing the developers’ incredible attention to detail and the motivation to constantly expand the world-building. It serves as a gateway to the massive world of Arknights for new players while providing creatively appealing details for long-time fans.
An Awesome Addition for the Arknights Player Base
In conclusion, this mode ticks all the boxes, benefiting both veteran and new players by offering an experience that is both fresh and familiar. It is no surprise that it has been a resounding success within the Arknights community. Following overwhelmingly positive responses after just two seasons, there are already reports that it will soon become a permanent addition into the main game.
Arknights
Publisher: Hypergryph (China), Yostar (Global)
Developer: Hypergryph, Studio Montagne
Platforms: Android, iOS, Windows
Release Date: 16 January 2020
Genres: Tactical role-playing, tower defense
PEGI: 16
