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Rarest Steam achievement in Quantum Conundrum

Rarest Steam achievement in Quantum Conundrum
Who
In less than 12 parsecs
What
0.6 percentage
Where
Not Applicable
When
13 December 2016

Only 0.6% of Quantum Conundrum (2012) PC players have unlocked the “In less than 12 parsecs” achievement, which involves achieving goal times on all of the non-DLC maps.

This is the rarest steam achievement for the core game, and doesn't include DLC achievements (which may not have been purchased by many players). The rarest achievement, including DLC, is "Two Drink Minimum" for meeting all the Shift Goals in "The Desmond Debacle."