The Epoch medal is awarded for completing a certain number of hackstreak cycles.

The first hack performed on any given day (local time) will increment your current hackstreak. (Drone hacks do not count.) Reaching a streak of seven days completes a cycle, which earns progress toward this medal. Missing a day only resets your current cycle; it has no effect on the number of cycles you’ve completed for the medal.

Tier Cycles
Bronze 2
Silver 4
Gold 8
Platinum 30
Onyx 60