Challenges completed by Blu
Flipper Waluigi : Prendre le Jump qui n'est pas sur la piste

Flipper Waluigi : Trouve le boost qui n'est pas sur la piste.

Jump on the Mushroom
Rainbow Road : So let's all jump up super high! High up in the sky! There's no power-up like dancing... I'll stop.

Mario Team Racing
Cyborg Speedway : Finish in the 1st position in VS mode, in medium mode, with Mario, with 12 participants

Indentium
Cyborg Speedway : Reach the little indent near the end of the track without falling

A Secret Shortcut that will help you in the Time Trial Challenge (Y'know, once it's validated)
Cyborg Speedway : Reach the 2nd Boost Panel without falling

pc race
Race Day : Finish in the 1st position

Race Time
Race Day : Finish in the 1st position

Emerald Pun
Crystal Mines : Locate the Emerald in 7th place

Ruby Goldberg Machine
Crystal Mines : Locate the Ruby without touching item boxes

CTR-esque Shortcut
Clockwork Dunes : Reach the Boost Pad in less than 12s, without using any item

Morton Koopa
N64 Kalimari Desert(OG) : Complete the track

FAILING THE SHOWDOWN!
Duel Dimension : Complete the track in VS mode, with 2 participants, in 2nd place
In difficult mode

No! ...rth.
Duel Dimension : Fall in the Northern-Most part of the map

SHOWDOWN!
Duel Dimension : Finish in the 1st position in VS mode, with 2 participants
In difficult mode

Shiny but Deadly
Duel Dimension : Go in the Off-road Crystal stuff near the start without falling

Just go to the workshop 🏭🏭🏭
The lotus workshop : Complete the track without using any item, by falling at most 2 times

Now, you have to work hard 🔧🔧🔧
The lotus workshop : Finish in the 1st position in VS mode, by falling at most 1 time
With 8 participants, no teams

Jump, jump little Donkey-kong
The lotus workshop : jump on all gears with Donkey-kong

Sapphire Extinguisher
Crystal Mines : Locate the Sapphire without drifting
