N2+3H2→2NH3 is the final stage in Summer Lesson.


  • The stage begins with a St. Pigge the 2nd, followed by three Pigges.
  • After 40 seconds, an Owlbrow spawns, with another one spawning 10~13.3 seconds later.
  • After 100 seconds, Pigge starts spawning in 30~50-second intervals.
  • When the enemy base is attacked, Doge Dark, Teacher A., Shadow Boxer K and Gory Junior emerge.
    • Doge Dark continues to spawn in 6.7~13.3-second intervals, while Gory Junior spawns in 16.7~23.3-second intervals. In total, there are 17 Doge Darks and 6 Gory Juniors.
    • After 20 seconds, another Teacher A. is spawned, and after 30 seconds, another Shadow Boxer K spawns.



Celebration Events
Sweetest Sorrow Mallow MarchMarzi PainCavity Creeping
All Hallows Road Sweet SamhainLantern O'JackCosplay CarnivalTrick or TreatmentHello Hello HalloweenHarvest Festival
Jolly St. Nick Coming to Town!Reindeer GamesWhipped CreamCoup d'WorkshopWar on Xmas
Summer Diary Short ShortsSquirtgun WarfareCandy Apple DentistryMosquito HellSparkler HeavenBackyard BBQ
A Cultured Festival Meatless WienersDeep Fried AirBurnt to PerfectionNot Quite OrganicOutta Change...Always In the Red
Cats in the Snow Langue de ChatWhite DoveSnow at DawnBuddha of RomanceIcy Desire
Day of the Cat Savage InstinctBloodstained ClawsThe 222 Incident
Spring Sprang Sprung Season of RebirthBunny Bros.Island Egg HuntNative CulturesMost AncientRongorongo
The Midas Touch Gold in a Coal MineI My Me MinerGolden Age's DawnNever Not Shovelin'Dreams Come False
Sliming to Victory Rainy Day RacesTinpot TrophyStormcloud StakesParadise DerbySlimy Stallions
Summer Lesson Kids At SchoolI Am A Catc2 = a2 + b2War of the RosesN2+3H2→2NH3
Silver Week No Shame in 2ndSilver AnniversaryA Distant Road
Go Go Graduates! Pencil LauncherDemon Drill SgtOne-Use CannonSanitary CorpsCat Army's Day Off
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