First make the party Mario/Peach/Mallow.
EQUIP Mario:
Amulet
EQUIP Peach:
Safety Ring
EQUIP Mallow:
Troopa Pin
Jump on the spinning bolt, and jump straight up and down two times to get it far enough to then jump to the other side.
More spinning bolts. Jump 5 times on the first bolt before jumping to the next platform.
Take the upper-right path and jump 2 times on this bolt before jumping to the next platform.
On the last bolt, if you jump from the edge of the spinning bolt then you can jump immediately to the final section and continue to the next screen.
Run directly to the top and hit the green button, then exit out the right path that opens.
There is a hidden chest in the left corner with a recovery mushroom if you need it.
Safety save here before continuing for the upcoming fight!
Jump on the spring to launch up to the bolts.
Jump one time on the first bolt, then jump straight to the end nut.
Jump onto the second bolt and you can jump immediately to the ledge.
Take the spring down to fight...
Mallow uses Thunderbolt, Mario uses Ultra Jump on Countdown, Peach uses Group hug if needed, if not, use Rock Candies with her (about 3 if you can)
Mallow use Thunderbolt, Mario uses Ultra Jump on countdown, Peach same process.
After the bells fall, Mallow use Shocker on Countdown, Mario attack Countdown, Peach defend or Group Hug.
Mario uses Rock Candy for two turns in a row, then he attacks Countdown every turn after that with his Lazy Shell.
Mallow uses Thunderbolt every turn until all bells on the side die, then when only Countdown remains, finish him with Shocker.
Peach uses Group Hug when needed, or Defend.
If Countdown uses Recover or Mega-recover on a bell, have Mario attack that bell instead of Countdown for that turn only.
Good RNG in this fight is if attacks and Death Roulette are focused on Peach.
Good RNG is also to freebie Rock Candy.
Make the party of Mario/Geno/Mallow.
EQUIP Mario:
Troopa Pin
EQUIP Mallow:
Amulet
EQUIP Geno:
Feather
Safety save afterwards if you want, and keep going to the next room.
Line yourself up with the lower edge of the screen as you go.
Jump on the first conveyor belt as far forward as you can, and run under the second conveyor belt.
Take the platform over. Instead of switching to the second platform, you can actually jump from the furthest point on the first platform to the next ledge.
Jump over the next conveyor belt and head up and right to proceed.
On this screen, there are Bowyer arrows raining down on you which will stun you and possibly make you run into some machine fights. Be careful!
To avoid the arrows, jump on the conveyor belts and use them to carry you a little further faster. The arrows will miss you if they come when you're on the belts.
This screen has some tough platforming. You need to stay on the conveyor belts and get across, then manoeuvre some tight passages while avoiding roaming enemies.
After the first set of ghosts, don't head up-right! Head left to the conveyor belts to continue, and take the platforms across.
More tough platforming. Jump up the conveyor belt stairs as fast as you can, but you will almost certainly run into a machine Bowyer enemy. Don't worry, you can just run from these guys even though it looks like a boss.
After the first conveyor stairs, there is a narrow section where you have to jump over machine Axems. You can practice this room to get faster, but it's more important to be safe! Go slow if you must! The Axem encounters here are very bad so it's better to go slower and avoid them than to get hit.
One more conveyor belt staircase with a Mack machine enemy. You can wait for one to pass, then jump up as fast as possible to avoid it.
Holy crap safety save YES!
This fight is unavoidable, so jump into him to start.
Mario attacks.
Geno attacks.
Mallow uses Shocker.
Lather, rise, repeat.
Switch the party back to Mario/Peach/Geno.
Don't go down the hole just yet. Head up to find a room with two chests.
Grab the top one first for a flower, then the bottom one for a recovery mushroom.
Now head back to the Yaridovich room and fall down the hole when it's clear to fight...
Use Geno Boost on Mario and then on Geno.
Mario attack the magician Domino.
Peach group hug if needed.
After Geno is done boosting, have him attack the magician as well. After the first part of the fight is over...
Have Mario and Geno focus all attacks on the snake. Do not attack Cloaker at all!
Peach use Group Hug/Pick Me Ups/Syrups if needed.
Before heading into the factory, make your party Mario/Mallow/Geno.
EQUIP Mario:
Amulet
EQUIP Mallow:
Troopa Pin
EQUIP Geno:
Feather
After the fight, run up-left to enter the factory and the final fights of the game!