Here is the full list of all 19 Road Doom achievements.
15 Doom Orbs at once!
Enter the Desert world.
Enter the Void world.
Enter the Magma world.
Enter the lair of the four horsemen.
Finish the tutorial.
Beat the game without taking any damage.
Unlock all your skills.
Beat the game without purchasing any skills.
Summon 5 Energized Ponds in one stage.
Turn 10 enemies to stone with a single use of the Medusa spell.
Defeat the Four Horsemen in Boss Run.
Defeat the Four Horsemen in Story.
Beat Story in "HAHAHA" difficulty.
Defeat Rival in Desert world.
Defeat the Mothership.
Defeat Rival in Void world.
Defeat the Void King.
Defeat Rival in Magma world.