Mercury Hg
21 Achievements
0-0h
PS3
Gravisium
Complete all the Discovery Mode levels in the Heavy Elements content pack.
7.1%
How to unlock the Gravisium achievement in Mercury Hg - Definitive Guide
themegamancave
TrueAchievements
TrueAchievements
This one is just as easy as it sounds, simply complete every level in the Heavy Elements pack. You do not need to complete every challenge in each level, just reach the goal at the end of the level. If you've completed the original game discovery levels, this should be no problem for you!