Call of Duty: Modern Warfare 4 offers largely identical core content on Xbox Series X|S and PS5, but the rewards for full completion differ between the two achievement systems. Players report that completing all 18 achievements on the Xbox version unlocks the Mythic Achievement within the shared Call of Duty app, whereas the PS5 version does not offer a Platinum trophy.
Microsoft recently introduced the Mythic Achievement to honor players who complete all base achievements in a game. Content added through subsequent DLCs or updates is typically not required for unlocking this achievement. The system can also retroactively recognize eligible games that players have already completed.
The achievements for Call of Duty: Modern Warfare 4 are technically listed as add-ons within the Call of Duty HQ app, yet they still qualify for the Mythic Achievement. Microsoft and Activision have not provided specific details on this determination. The PS5 version also features 18 trophies, including 8 gold and 10 silver, but since the trophy list is categorized under an existing app's add-on section, no Platinum trophy has been included.
Completing the full set of achievements on the Xbox version is estimated to take at least 15 hours. The main challenge lies in finishing the campaign on "Realistic" difficulty, which removes the HUD and increases combat pressure. Players must also complete specific combat challenges and collection tasks. While platform differences do not alter the game itself, they may influence the choices of players who prioritize full achievement completion or Platinum trophy records.