20 — Silk Road

By far the hardest sub-chapter to this point — eight stages, eight different problems. The wiki's recommendation: most or all Crazed Cats and True Form Normals.

The saga's first true gear-check. Every stage requires a different strategy, so expect to rebuild your lineup constantly. The two most notorious: Marco Po Road, near-unbeatable if you can't win fast (Teacher Bun Bun plus an enemy base with enormous HP — the classic cheese is Li'l Tank Cat), and Godiego Pass with three Dober P.D.s, mercifully alongside Shadow Boxer Ks you can farm for cash.

Four enemy introductions: Ginger Snache, a fast Red knockback-puppet who swarms in groups; Wall Doge, the enemy's answer to your own Wall Cat — high health, no offense, pure stall; Sunfish Jones, an Angel with massive health, exceptional range, and a slow on hit; and Super Metal Hippoe's Stories of Legend debut, a fast Metal with guaranteed knockback per hit. (The stage names are one long Journey to the West / Godiego medley.)