Main Chapters · Stage 21
Cats of the Cosmos Ch. 3 — Stage 21
アルデバラン
Cats of the Cosmos Ch. 3 — Stage 21 is a Battle Cats stage in Cats of the Cosmos Ch. 3. It costs 93 energy and sends 6 enemy spawn lines against a 520,000 HP enemy base, and clearing it rewards 7,000 XP. Its enemies carry the Red, Alien and Floating traits, so cats that target them do the most work here.
Data updated: 2026-08-31
93Energy Cost
7,000XP Reward
520,000Enemy Base HP
5,000Stage Length
10Max Enemies
9.2Difficulty
Enemy spawns (6)
| Enemy | Strength | Count | First Spawn | Respawn | Base HP Trigger | Notes |
|---|---|---|---|---|---|---|
 B.B.Bunny | 2600% | ∞ | 3.3s | 13.3s~20s | 100% | — |
 Imperator Sael | 1800% | 3 | 6.7s | 16.7s~23.3s | 100% | — |
 Shy Boy | 1600% | 1 | 13.3s | — | 100% | — |
 Gardeneel Bros. | 150% | 1 | 16.7s | — | 100% | — |
 Spacefish Jones | 500% | 1 | 18.7s | — | 100% | — |
 Ms. Sign | 100% | ∞ | 900s | 900s | 100% | — |