Here is the full list of all 21 Gemini: Heroes Reborn achievements.
Completed Temporal Loop
Sisters
TK Throw 1000 Things
Dug Deeper
Find 30 Secrets
Catch 10 Rockets
Best Friends Forever
Found What You Were Looking For
Escaped the Prison
Made it to the Elevator
Uncovered Alex
Package Delivered
Survived the Elevator Battle
Introduced to Mason
Kill a dozen enemies via Deathtraps
Learned Time Stop
You Died
Learned Telekinesis
Learned Time Scout and Time Shift
Finished the Opening Tutorial