World 7 - Level 2
Be warned that this level requires strong nerves!
Stinky can only leave the gate for a very short time, or both of them will be locked out. Anytime Stinky leaves the gate, Stinky's job has to be done very quickly, with enough time for Stinky to get back into the gate before it closes. Do so and move the bottom boulder up and left along the yellow arrow (take two "turns" if you need it).
Switch to Loof and quickly collect the Rainbow Coins in the yellow circle, then move to the yellow "X". Dash left to the light blue "X", and collect Rainbow Coins along the green path. Wait for the fireballs to quiet down before collecting the final coin. Get back to the blue "X", and a push the boulder down, then immediately start running to the right, pushing and following another boulder in your way. Position Loof at the white "X".
Dash out of the gate with Stinky again and roll the boulder along the white arrow. Switch back to Loof and roll two boulders along the dark blue arrows. Run along the purple path to collect the remaining Rainbow Coins. The Bonus Coins are now within reach - and protected from fireballs!