Here is the full list of all 48 Sonic Forces achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Collected all Silver Moon Rings in Shadow's Story.
Collected all Number Rings in Shadow's Story.
Collected all Red Star Rings in Shadow's Story.
Collected 30 Wispons
Collected Silver Moon Rings three times
Collected Number Rings three times
Defeated 5,000 enemies
Created your second Avatar
Completed 10 Daily Missions
Restored peace to the world
Completed 10 SOS Missions
Collected a total of 10,000 rings. (All Rings held at the end of the stage will be counted.)
Defeated Infinite
Cleared all Secret Stages
Turned the tide of the conflict
Completed 5 Daily Missions
Completed 5 SOS Missions
Achieved a soldier's highest honor
Drove off Infinite again
Collected 10 Wispons
Liberated a world
Used the Closet
Equipped a part in every slot
Collected 100 parts
Completed your first SOS Mission
Drove off Eggman
Drove off Infinite
Defeated 1,000 enemies
Changed Wispons for the first time
Collected 50 parts
Defeated Zavok
Completed 3 Daily Missions
Made it into the rankings
Utilized the Rental Avatar function
Created an Avatar
Cleared Stage 1
Cleared all EX Stages
Collected all Red Star Rings
Collected all Number Rings
Collected all Silver Moon Rings
Collected a total of 50,000 rings. (All Rings held at the end of the stage will be counted.)
Collected a total of 100,000 rings. (All Rings held at the end of the stage will be counted.)
Defeated 10,000 enemies
Achieved highest honors with all races
Collected all Wispons
Collected 500 parts
Collected all parts
Completed all Challenge Missions