3-21 ALDEBARAN
3-21 Aldebaran is the 21st stage of Cosmos Ch.3 — Even Stars Burn Out. Previous stage: 3-20 Vega. Next stage: 3-22 Betelgeuse.
Spacefish Jones carries a Barrier (up to 12,000 HP) — your hits are absorbed until it's broken.
LI'L GROSS CAT B 30% Barrier Breaker. Also fits “Counter Alien.” 
SPACE CAT A 50% Barrier Breaker. 
FENCER CAT A Guaranteed 100% Barrier Breaker at long range — the reliable accessible breaker. 
TEKACHI A 100% chance to break Barriers. Also fits “Counter Alien.” 
LUMINA S 100% Barrier Breaker opens Star Alien Barriers for the team. Also fits “Counter Alien.” 
SKIRT CAT B 30% Barrier Breaker. Imperator Sael, Gardeneel Bros. and Spacefish Jones are Alien. Anti-Alien units take less damage and deal more.
GROSS CAT A Its True Form is Strong Against Alien, giving budget anti-Alien value. LI'L GROSS CAT B True Form has a 30% Knockback vs Alien. Also fits “Break the Barrier.” 
BAKERY CAT A Curses Alien enemies. 
LITTLE LEAGUER CAT S Resistant vs Alien and Long Distance — a budget anti-Alien backliner. Also fits “Break the Barrier.” TEKACHI A Resists and dodges Alien attacks. Also fits “Break the Barrier.” B.B.Bunny and Shy Boy are Red. Anti-Red units take less damage and deal more.
FISH CAT A Strong Against Red and tanky for the cost — a sturdy anti-Red frontliner. 
BEAN CATS B Knockback and (True) Resist vs Red enemies. 
CARPENTER CAT A Resistant to Red — durable against Red attackers. Also fits “Counter Floating.” 
APPLE CAT A Freezes Red enemies (100% in True Form). 
THE WHITE RABBIT S Slow, Strong and Weaken vs Red. Also fits “Counter Alien.” Shy Boy and Spacefish Jones are Floating. Anti-Floating units take less damage and deal more.
CARPENTER CAT A Resistant to Floating — durable against Floating attackers. Also fits “Counter Red.” 
BODHISATTVA CAT A Slows and (True) Weakens Floating enemies. TEKACHI A Resists and dodges Floating attacks. Also fits “Break the Barrier.” 
HIGH LORD BABEL S Equally tough against Floating enemies, with Colossus Slayer. Also fits “Counter Red.” 
ARCHER CAT A Deals Massive Damage to Floating enemies. Long-distance snipers at 1700~1950 range with Forward Warp. Can be ABUSED: their warp teleports your rushers past entire enemy formations.
Spacefish Jones replaces Star Peng as the backline ranged threat. Gardeneel Bros. adds an extreme-range (1700-1950) Forward-Warp sniper. Plus B.B.Bunny and Imperator Sael in the front. Row 1 restriction stays. r/battlecats: 'Aldebaran 3 is the stage that broke a lot of established Cosmos lineups when Ch.3 launched — the forward-warp from Gardeneel makes you panic.' Lineup (Row 1 only): Anti-Alien Barrier Breaker (Loincloth Cat, Bazibon) → Slime Cat or any Wave Attacker for Gardeneel Bros. snipe → Anti-Alien Uber backline (Lumina, Bazibastra) → Manic Mohawk frontline. Common failure: not knowing Gardeneel's forward-warp can be ABUSED — placed correctly, it teleports your A. Bahamut past the enemy formation. Most players learn this the hard way after the third or fourth retry.
The castle you destroy to clear the stage.