Floor Is Lava Cavern Mode: Hearts, Bats & Mine Carts
Cavern trades the usual straight-up climb for sideways cave sections — a horizontal wall of lava chasing you past bats, vines, and mine-cart rails, with a heart system instead of instant death.
What it does
Cavern can be played as its own standalone mode from the mode wheel, and horizontal cavern sections also interrupt normal Climber and Story runs from time to time. You enter through a marked opening platform and exit through a matching opening, which hands you back to the normal vertical climb where you left off.
Instead of one hit meaning death, you get up to 5 hearts per horizontal section (refilled to full each time you enter one, except during Story Mode where hearts carry over as a shared pool). Bats cost you 1 heart per hit, with a short cooldown between hits so you're not chain-hit by the same bat. Vines let you swing Tarzan-style and release early if you time it right. The lava wall itself moves faster than normal vertical lava and gives you a short head start, so the pressure to keep moving is real. Run out of hearts and it's game over — but clearing a whole section without losing a single heart pays a 100-coin perfect-clear bonus.
Mine carts are the other big Cavern feature: riding one makes you briefly invincible and converts whatever vertical power-up you're holding into a sideways ride distance instead (for example, a Lava Ship power-up becomes a long 50-unit cart ride, while a Torch Battery just stays a torch). The ride ends by launching you back upward to continue climbing.
How to play it
- Select Cavern on the home screen's mode wheel to play it directly, or just keep climbing in Climber or Story — a horizontal section will trigger on its own from time to time.
- Enter through the marked opening platform when a cavern section appears.
- Dodge bats and the advancing lava wall, use vines to swing across gaps, and hop into mine carts when you can for a free invincible ride.
- Reach the exit opening to return to your normal vertical climb with your prior progress intact.
Tips
- Bats have a short cooldown after hitting you, so a single bat can't drain multiple hearts back to back — but multiple bats can.
- Clearing a section with zero hearts lost pays a 100-coin perfect-clear bonus, so it's worth playing cautiously if you're near full hearts.
- Jump into mine carts whenever you get the chance — you're invincible for the ride and it covers ground fast.
- In Story Mode, hearts carry over between cavern sections instead of refilling, so pace yourself across the whole episode rather than each section in isolation.