Here is the full list of all 20 Magnetic By Nature achievements.
Beat Zones 1-4
Die twice within 3 seconds
Beat Zone 5
Beat zones 1-4 in speedrun mode in under 1 Hour 30 Minutes
Beat zones 1-5 in speedrun mode in under 2 Hours
Visit all 4 hidden levels
Get 100% collectibles
Stay moving in a level for 5 minutes
Beat zones 1-4 in speedrun mode while wearing Polarised Skin
Beat zones 1-5 in speedrun mode while wearing Polarised Skin
Touch the ground for less than 15 minutes total in a speedrun
Collect every collectible, beat every level, complete both speedrun modes, and visit ever hidden level
Beat a level in under 3 seconds
Beat zone 1 on a speedrun without dying
Beat zone 2 on a speedrun without dying
Beat zone 3 on a speedrun without dying
Beat zone 4 on a speedrun without dying
Beat zone 5 on a speedrun without dying
Beat zones 1-4 in speedrun mode without dying
Beat zones 1-5 in speedrun mode without dying