Principal's Rebellion

UL 20-4 is the fourth stage in UL 20.

Battleground

 * 30 Those Guys spawn, delay 0.07~2 seconds2~60f.
 * After 12 seconds, 3 Shadow Boxer Ks spawn, delay 4~8 seconds.
 * After 33.3 seconds1000f, infinite Hippoes spawn, delay 20~40 seconds.
 * On base hit, Bun Bun Black spawns as the boss with:
 * 1 J.K Bun Bun
 * 1 Bore.
 * 5 Ribbos, delay 16.7~20 seconds500~600f.
 * 2 Corporal Weylands, delay 50 seconds.
 * Infinite Kang Roos, delay 20~40 seconds.
 * Infinite Those Guys, delay 0.07~2 seconds2~60f.

Reference

 * https://cdn.discordapp.com/attachments/647391020455297034/649161948952264715/unknown-9.png