Mega Crit has shared a deep dive into the development of Slay the Spire 2, specifically focusing on the design and animation of the game’s latest boss: Aeonglass. Replacing the previously seen Doormaker, Aeonglass is a mechanical, multi-faceted creature that required unique technical solutions to bring to life.

Quick Facts

  • New Boss: Aeonglass, an hourglass-themed entity, has officially replaced the Doormaker.
  • Animation Techniques: The boss uses a custom shader to simulate "lava lamp" goo within its hourglass body and features independently timed rotating rings.
  • Merchandise Deadline: The current Makeship x Slay the Spire collection closes on August 1st, 2026, at 5 AM PST.
  • New Figures: Youtooz figures of the Necrobinder and Regent are now available for purchase.

The Development of Aeonglass

According to animator Chris, the design for Aeonglass evolved from a "Swiss Army rock" concept—a multi-faceted pillar capable of rotating sections to reveal different capabilities. Once the final art was established, the team faced the challenge of simulating 3D rotation within 2D software. To achieve the desired "attitude," the team shifted from a fixed, atom-like ring formation to a horizontal disk shape, which better suggests the sweeping motion of the boss's attacks.

Technical hurdles were significant, particularly regarding the boss's internal "time globs." To avoid traditional sand-like movement, the developers utilized a shader originally created for the "Living Smog" enemy. Because the animation software does not natively support these shaders, the animators worked with striped placeholders during production, which are replaced by the final liquid effect in-engine.

Furthermore, the rotating rings operate on a separate timeline from the rest of the character model. This allows Aeonglass to perform complex actions like debuffing players or responding to damage without interrupting the fluid rotation of its rings.

Merch and Community Updates

In addition to the development update, Mega Crit has expanded the game's physical footprint with new collectibles:

  • Makeship Collaboration: Patrons can pre-order a plush keychain of the Merchant's Courier, pins of his wares, and a plush replica of the Merchant and his rug. These are limited-time items ending August 1st.
  • Youtooz Figures: Vinyl figures of the Necrobinder and Regent are available for purchase via the Youtooz website.
  • Heave Ho 2 Crossover: The Ironclad has been added as a playable character in Heave Ho 2, which recently launched on Steam.

The studio also issued a call for fan art for next month's "Slay the Summer - Festival Edition" theme. Submissions must be 800x450px, text-free, and sent to [email protected] or the official Discord channel by Friday, August 7th.