Item description:

I think that you can unlock quickly several trophies with it. If you are lucky, some trophies will pop in the menu. If not, try to launch a cup and win it. Find a shortcut in a race, be careful to activate one time the slime and use every power up that you have to finally use the custom power.
Look what trophys will pop after your victory. If you need it, win a cup in the 2 others difficulty. And go to arena, play one match in the arena for the 2 trophys.

- EYES ON ME
Win a victory lap.

- BABY THROTTLE
Win your first race.

- ANCHORS AWEIGH
Win a Cup in easy mode.

- A BABY'S DUTY
Win all Cups in easy mode.

- GOING STRONG
Win a Cup in Normal mode.

- BOUND FOR GLORY
Win all Cups in Normal mode.

- A BABY'S GOTTA DO WHAT A BABY'S GOTTA DO
Use boost for the first time.

- JACK OF ALL TRADES
Play as each racer at least once.

- ALL-STAR TEAM
Win with all racers.

- SLIMED!
Activate the Slime valve for the first time.

- SLIME-MANIA
Activate the Slime in all the locations.

- SLIME MY RIDE
Use a custom power up for the first time.

- POWERFUL
Use custom power ups for all the racers.

- MAKE PAPA STU PROUD
Modify your kart for the first time.

- WARRIOR
Compete in the Arena for the first time.

- HEAVYWEIGHT CHAMPION
Compete 10 times in each Arena mode.

-DAS SUBWAY
Find a shortcut.

-SLIME RIDER
Put in the miles on the jetski.

-GETTING GOOD AT THIS
Win a Cup in Expert mode.

-THE BEST AROUND
Win all Cups in Expert mode.

-CHAMP
Win 9 victory laps.

-MOGUL
Unlock every upgrade in the store.