2-1 EARTH
2-1 Earth is the 1st stage of Cosmos Ch.2 — The Passion of Catgod. Next stage: 2-2 Mars.
UltraBaaBaa carries a Barrier (up to 266,000 HP) — your hits are absorbed until it's broken.
UltraBaaBaa's 266,000 Barrier needs a guaranteed 100% Barrier Breaker — chance-based units stall and waste your damage window.
FENCER CAT A Guaranteed 100% Barrier Breaker at long range — the reliable accessible breaker. Also fits “Out-range UltraBaaBaa.” 
MIZLI S 100% chance to break Alien Barriers. Also fits “Counter Alien.” 
LUMINA S 100% Barrier Breaker opens Star Alien Barriers for the team. Also fits “Counter Alien.” 
BORA S 100% Barrier Breaker reliably cracks Star Alien Barriers. Also fits “Counter Alien.” 
GRAVI S 100% chance to break Barriers. Also fits “Counter Alien.” 
KOMORI S 100% chance to break Barriers. Also fits “Counter Alien.” 
UltraBaaBaa is 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. Also fits “Out-range UltraBaaBaa.” 
LI'L GROSS CAT B True Form has a 30% Knockback vs Alien. Also fits “Break the Barrier.” 
BAKERY CAT A Curses Alien enemies. Also fits “Out-range UltraBaaBaa.” 
MITER SAW CAT A Resistant to Alien and deals Massive Damage to Alien. Also fits “Break the Barrier.” MIZLI S KB, Slow, Resistant and Barrier break all vs Alien. Also fits “Break the Barrier.” UltraBaaBaa reaches 110 range. Units that out-range it can chip safely without taking hits.
GROSS CAT A Range 350 — fires from beyond its 110. Also fits “Counter Alien.” LI'L GROSS CAT B Range 300 — fires from beyond its 110. Also fits “Break the Barrier.” 
PSYCHOCAT A Range 365 — fires from beyond its 110. Also fits “Counter Alien.” 
CAT TOASTER A Range 330 — fires from beyond its 110. Also fits “Break the Barrier.” MIZLI S Range 450 — fires from beyond its 110. Also fits “Break the Barrier.” UltraBaaBaa debuts as Ch.2's opening wall — 266,000-HP Barrier (the largest in the game) protecting very low actual HP. Until the Barrier cracks, your damage does nothing. Bazifenix's 100% Barrier Breaker is the cleanest solution; Loincloth Cat (Special) is the budget fallback. Once the Barrier breaks, any Anti-Alien attacker finishes UltraBaaBaa in seconds.
Ch.2 reset: UltraBaaBaa replaces Shibalien Elite as the boss. 266,000-damage Barrier — the largest in the game — protects very low HP. r/battlecats's standing rule: don't attempt this stage without a tested Anti-Alien Barrier Breaker. The Barrier doesn't decay; every hit during it bounces for 1. Required: Bazibon line, Loincloth Cat, or talented Crazed Bahamut. King Dragon Cat works at lower investment. Pair with Mohawk + Manic Mohawk + 1-2 Anti-Alien Ubers for support. Common failure: attempting Ch.2 without ever clearing an UltraBaaBaa stage in ItF first. If you've never broken a 266k Barrier, this is the wrong place to learn.
The castle you destroy to clear the stage.