3-45 N77 NEBULA
3-45 N77 Nebula is the 45th stage of Cosmos Ch.3 — Even Stars Burn Out. Previous stage: 3-44 Crimson Star. Next stage: 3-46 Andromeda.
UltraBaaBaa and Ribbo carry Barriers (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. 
BORA S 100% Barrier Breaker reliably cracks Star Alien Barriers. Also fits “Counter Alien.” 
LUMINA S 100% Barrier Breaker opens Star Alien Barriers for the team. 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.” 
MIZLI S 100% chance to break Alien Barriers. Also fits “Counter Alien.” 
UltraBaaBaa, Project A, Ribbo and Star Peng 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.” 
WHEEL CAT A Deals Massive Damage to Alien enemies — a huge area nuke against Alien crowds and bosses. Also fits “Clear the crowd.” 
MITER SAW CAT A Resistant to Alien and deals Massive Damage to Alien. Also fits “Break the Barrier.” 
CATMAN S Deals Massive Damage to Alien in every form. Also fits “Clear the crowd.” 8 enemy types stack up here. Area attackers hit the whole push at once instead of one unit at a time.
VALKYRIE CAT A Hits the whole group while it freezes them. WHEEL CAT A Hits every Alien in a wide area at once, melting grouped Star Aliens. Also fits “Counter Alien.” 
SURFER CAT A Area damage hits grouped enemies. Also fits “Counter Alien.” CATMAN S Long-range Area damage clears groups. Also fits “Counter Alien.” 
ACTRESS CAT B Hits multiple enemies at once for budget crowd damage. Ribbo's 65k Barrier + 100% Warp at 400~550 range. Snipe with waves (Major Leaguer Cat).
Ribbo + UltraBaaBaa + Project A + Star Peng — considered by some players the worst stage in CotC, full stop. The ROW1 restriction means you can't backline. All four bosses are at endgame magnifications. Community fix: guaranteed Barrier Breaker (Ganglion) for both UltraBaaBaa and Ribbo, Warp Immune meatshields (Manic Mohawk), A. Bahamut for Project A, and an Anti-Alien LR (Lumina) as the tank. Some players consider this harder than 3-47 Black Hole. Common failure: not bringing both Barrier Breakers AND Warp Immune. Single-solution lineups die.
The castle you destroy to clear the stage.