Overview

100days is a compact but surprisingly deep roguelike auto-battler that launched on Steam on October 16, 2026. Developed and published by the duo CeciliaR and 白天, this paid title blends the visual charm of HD-2D graphics with the strategic chaos of bullet-hell combat.

The core loop is simple: survive endless days, each one throwing stronger enemies at you, while you build a loadout that can keep up.

Highlights

  • Six Simultaneous Weapons: Equip up to six weapons that all fire at once, creating a dense, bullet-hell-style screen presence that feels both overwhelming and satisfying.
  • 300+ Elemental Effects: Combine elemental tags on your weapons to trigger a huge variety of combat effects. The description promises over 300 possible interactions, meaning every run can feel genuinely different.
  • Roguelike Progression: After each level, you pick one of three upgrades. This simple choice system, combined with the endless-day structure, encourages experimentation and replayability.

Who It's For

If you enjoy idle-adjacent games that still require tactical thinking, or if you like roguelites where builds emerge from small decisions, 100days is worth a look. The auto-battler format means you can watch your setup unfold, but the bullet-hell density keeps you engaged.

It's also a good pick for players who want a relaxing yet strategic experience—the game is tagged as Casual and Relaxing, so it's not about twitch reflexes.

Game Info

  • Genre: Casual, Relaxing, Singleplayer, Roguelike, Incremental, Bullet Hell
  • Developer/Publisher: CeciliaR, 白天
  • Release Date: October 16, 2026
  • Modes: Singleplayer (with some Steam features listed, but core is solo)
  • Languages: Simplified Chinese, English, Japanese, Korean
  • Price: Paid title (check the latest Steam listing for current pricing)

100days is a fresh take on the auto-battler formula, packing a lot of variety into a seemingly simple package. If you're curious about how six weapons and elemental tags can create hundreds of combinations, this is a game that invites you to lose track of time—one day at a time.