Here is the full list of all 47 Splasher achievements.
Go Splashteam
Get your first Medal in Time Attack
Get your first Gold Medal in Time Attack
Complete a level without dying
Jump and you're history
Rescue all 154 Splashers in Standard mode
Complete the game in Standard mode
Mashed Potatroopers
Complete all the quarantine areas
Give yourself to the Dark Side
Lasers are my calling card
You should have held that door!
Get Bouncink
A good Potatrooper is a drowned Potatrooper!
A bird with two stones
At least I'm not the only one
A close shave
Off to a flying start
Fries anyone?
I get knocked out, but I get up again!
A good Potatrooper is a dead Potatrooper!
Get Water Stickink
It's all going splendidly
Rescue all the Splashers from a level in Standard mode
Get Water
All in a good cause
A friend in need is a friend indeed
You're never going to keep me down!
Why is it always me?
You rang milord?
Complete a level without jumping
699
Right time, right place
Two Splashers in the same place? Impossible.
Get your first Platinum Medal in Time Attack
Complete a Selfish Speedrun
Complete a Standard Speedrun
Complete a Gotta Catch'em All Speedrun
Get your first Medal in Speedrun
Get your first Gold Medal in Speedrun
Get your first Platinum Medal in Speedrun
Complete a Speedrun without dying a single time
Get all the Bronze Medals in the game
Get all the Silver Medals in the game
Get all the Gold Medals in the game
Get all the Platinum Medals in the game
Get all the Achievements. After that, you are definitely one of the best players on the planet, perhaps even the best ever! Continue to prove it in the leaderboards!