Bio Laboratory — Split Mushroom

Split Mushroom's stage, Bio Laboratory, is a research complex overrun since he took it over — moving platforms, shifting light-gates on a timer, and stretches that don't behave like solid ground. Watch the timing before committing to a jump through a gated section.

In the final corridor of Area 2 there's a gap in the ceiling on the right. Zero has no electric web to climb, so use Kuuenbu (the mid-air double jump from Split Mushroom) to reach the false platform and the Heart Tank above it — a backtrack once you've beaten Split Mushroom himself.