Season 5 introduces three new Agents — Rossweisse, Blazebell, and Dahlia — each with distinct playstyles centered on Light and Dark, Binding, and Purity, with Rossweisse pegged as the first anniversary seasonal Agent launching on October 21 alongside her Partner Sig.

The first 2-player co-op mode, Core Break, is due in December, offering duo play with pre-built Agents, random matchmaking, and joint tactical decisions including dice-determined outcomes, while the Corruption update remains postponed until polish milestones are reached.

Chaos Zero Nightmare marks its first anniversary with a special broadcast detailing updates, a quality-of-life overhaul, and a roadmap led by new Producer Choi Seung-hyun and Development Director Kim Ki-beom.

As part of the 1st anniversary, players with Level 10+ can choose an Agent/Partner via a Selector ticket (choices include Faye and Ruixiang), and the package includes 1,600 Crystals, 70 Regular Rescues, check-in rewards, Ether gifts, and a livestream coupon for 1,000 Crystals, plus merch raffles and retrospective events across social channels.

A new Battle Speed toggle arrives, Challenge mode offers three free plays per week with paid extra attempts, Divine Inspiration in Chaos Unidentified Areas applies to already Inspired cards, weekly missions pay out Cores, and UI/UX receives sticker UI enhancements along with new honor features.

Rossweisse’s concept centers on cycles and duality, featuring a Trauma Code with full voice work, and mechanics where cards split into Light and Dark that fuse into a powerful finisher.

Cosmetic expansion brings Special-tier Casual Wear starting with Rossweisse, replaces most visuals and expands voice lines, and Card Skins become official with an 'Invitation from the Night Sky' pack for 16 Agents; skins are agent-wide and future collaborations are planned.

overall, Season 5 broadens narrative, introduces major gameplay and QoL upgrades, enhances cosmetics and monetization, and rolls out a comprehensive anniversary celebration with events, charity activities, and new multiplayer content.

Season 5 redefines systems: Great Rift splits into Subjugation Battle and Merit Battle, adds an Action Pattern Preview to warn of boss actions, grants Partners new Exploration Passives, and overhauls Memory Fragments with main/sub-stats and a Reconfiguration feature.

Season 5, titled A Promise Upon the Snow, unfolds on the ark Frontnova after a crash on the polar planet Nivalis, introducing Celestial Bulwark as the new seasonal Chaos and delving deeper into gods and Chaos lore.

Blazebell, a Sileima faction Justice-attribute Controller, enhances action points, card draws, and damage via Binding and Purity, while Dahlia uses Binding to fuse effects into a single potent card.

The 1st anniversary theme song by Mitsukiyo (Studio ALO) and vocalist CielA debuts on October 20, with Chaos Zero Nightmare featuring at AGF 2026 in Korea alongside on-site activities and performances; collaboration cafes and merch programs span Japan, Korea, and China with partnerships including maidreamin and Prismlens, plus figures and major-brand merch.