100 Coins in Lethal Lava Land

Head to the arch and cross the first bridge to find the first Bully. Knock it into the lava and hope the coin flies onto the platform, so you can collect it (1 coin).

Head across the moving bridge and defeat the Mr. I there for another five coins (6 coins total).

Jump onto the crescent-shaped ramp nearby to get three coins, as well as five more from the “bridge” with the fluctuating lava (14 coins total).

Collect all eight Red Coins before the sliding Bowser puzzle (30 coins total). Once the puzzle completes itself once, five coins will pop out the middle of it (35 coins total).

Defeat the two Bullies before the platform with the Fire Bars and collect four coins on another crescent-shaped ramp (41 coins total).

Jump onto the platform with the spinning Fire Bars and onto the next submerging spot, where you can collect five more coins (46 coins total).

Defeat the three normal Bullies on the second Big Bully platform and collect the ring of coins (57 coins total).

Collect four coins on the square-shaped pieces that get submerged in lava (61 coins total).

Long Jump to the circular island with the Mr. I, where you get a Blue Coin from it, and collect eight more coins (74 coins total).

Grab the five coins from the bouncing box on the serpent-like walkway (79 coins total).

Collect the five coins on the little path leading to the volcano, then three more on the ring surrounding the volcano (87 coins total).

If you need more coins, return to the start and grab the Koopa shell from the yellow box. Collect five coins on one of the high brown ramps (the one by the three Bullies platform), as well as five more coins underneath the opening/closing bridge (97 coins total).

Go inside the volcano. Behind your starting position, there will be a single coin right before the elevator (98 coins total).

Use the elevators to get to the Elevator Tour star, where there are three coins right before it (101 coins total).

Jump back down towards the starting point of the volcano. Collect ten coins before the bit of the wall that drops down to try and crush you (111 coins total).

Collect five coins before the next Bully and lavafall, then five more on the thin ledge by the lavafall (121 coins total).