Multiple planets orbit the player, dealing damage to enemies they pass through. Damage scales with the number of coins collected during the current run — more coins means more powerful planet hits. This makes Celestial Booster the rare weapon where gold-collection playstyle directly translates into combat output. Level scaling increases planet count, orbit speed, and base damage.

Obtained by evolving Town Sword (a faced-direction melee weapon that can trigger the "Swallow Slice" technique). The planets orbit continuously, providing ambient damage without requiring aim or positioning adjustments.

Max Celestial Booster (Lv 8), carry the External Obstructor item, and open an elite-drop chest after 10:00 to evolve into Negative Space.

Negative Space Effect

After evolution secret planets begin appearing. Planets occasionally go "negative" — transitioning into an alternate state with different behavior and effects. Coin-collection damage scaling carries through to the evolution, making continued coin pickup mandatory.

• Coin-collection damage scaling grows continuously throughout the run
• Orbiting planets deliver constant ambient damage without aim requirement
• Coin-focused builds achieve high damage output earlier by actively collecting gold
• Post-evolution secret planets and negative state add bonus effects on top of the existing scaling

• Underperforms if coins are not actively collected during the run
• Requires evolving Town Sword first before obtaining
• Specific evolution item (External Obstructor) required
• Orbital melee range — limited coverage against distant enemies

• Characters with coin-collection bonuses: accelerate damage scaling
• Trouser: Greed bonus directly increases coin income, amplifying Celestial Booster's damage growth
• Imelda: +10% Growth speeds evolution

• External Obstructor: mandatory for evolution (top priority)
• Clover: improved drops increase coin pickup opportunities, accelerating damage scaling
• Candelabrador: wider area extends planet orbit radius and coverage
• Spinach: +10% Might raises base planet damage

• XI Celestial Dusting: coin collection bonus directly feeds Celestial Booster's damage scaling
• IX Divine Bloodline: crit compounding with continuous planet hits

• Early (0–10 min): Level Celestial Booster and actively collect coins — every coin feeds the damage scaling. Grab Clover to maximize coin opportunities.
• Mid (10–20 min): Secure External Obstructor and evolve at max level. Continue collecting coins through the evolution — the scaling persists post-evolution.
• Late (20+ min): Negative Space's secret planets and negative events stack on top of accumulated coin scaling. A coin-maxed late run makes the orbiting planets among the highest-damage ambient weapons available.

Q: How do I get Celestial Booster?
A: Evolve Town Sword — completing Town Sword's evolution unlocks Celestial Booster.

Q: How much does the coin scaling matter?
A: Damage scales directly with total coins collected in the run. A coin-focused build (Clover, Greed characters) achieves dramatically higher planet damage than a run without coin emphasis.

Q: What do negative planets do?
A: After evolving into Negative Space, planets occasionally enter a negative state with alternate behavior — typically granting bonus damage or special effects. The exact negative-state effects have a random element but consistently add value on top of the base scaling.