Despite receiving the same 4-star difficulty rating as the previous installment, XCOM 2 is arguably more difficult than XCOM: Enemy Unknown. A minimum of four playthroughs under difficult conditions is required, though players new to the series may require even more. While the Platinum is certainly doable, it requires much time, as well as strategy, patience, and plenty of trial and error.

Expect well over 100 hours of gameplay, even for veteran XCOM players.

To start things off, go ahead and play through the tutorial, which will unlock the First Blood trophy. Once you've gotten the trophy, it's a good idea to quit, delete the save file, and start your playthrough with the tutorial disabled. This is because you will lose lives during the tutorial which will cancel out getting The Untouchables trophy which requires beating the game without losing a life.

Now, there are two ways you can go about getting this Platinum; by either doing two playthroughs, or a minimum of four. Each playthrough will last between 25-30 hours. Getting the Platinum in two is only recommended to veteran XCOM players, and even then it will still be challenging.

If you wish to finish the game in two playthroughs, then your first will need to be on Legend difficulty with Ironman enabled, and without losing any lives. This will unlock both the Defender Of Humanity and Immortal Commander trophy for completing the game on Legend difficulty, the Valhalla trophy for beating the game with Ironman mode enabled (which autosaves during your playthrough) and The Untouchables trophy for beating the game without losing any lives.

During your second playthrough, focus on beating the game before July 1st for the Exquisite Timing trophy, avoid purchasing a Squad Size upgrade for The Few And The Proud trophy, and beat the final mission with only conventional gear for the Who Needs Tygan trophy.

However, if you wish to make things easier rather than quicker, than we recommend four playthroughs. In this case, your first playthrough should be on Commander difficulty and focusing on getting The Untouchables trophy. Your second playthrough, again on Commander difficulty, and beating the game by July 1 for the Exquisite Timing trophy. Your third playthrough should be still on Commander difficulty but with Ironman enabled for the Valhalla trophy. Finally, your fourth playthrough should be on Legend difficulty for the Immortal Commander trophy.

Once all those playthroughs are complete, it's simply a matter of mopping-up anything you may be missing. This may include completing an online match for The Most Dangerous Game trophy. Be sure to check out the XCOM 2 trophy guide links under our Links tab to see what you're missing and their requirements.

IGN has a Walkthrough here:
http://www.ign.com/wikis/xcom-2/Main_Missions

And a Walkthrough by Ferry Groenendijk:
https://www.videogamesblogger.com/2016/02/09/xcom-2-walkthrough.htm

Cassylvania has a great Trophy Guide here, which includes the DLC:
https://www.playstationtrophies.org/game/xcom-2/guide/

And a great Trophy Guide by Pixel-Zero:
https://psnprofiles.com/guide/5391-xcom-2-trophy-guide

And Ferry Groenendijk has a simple Trophy Guide here:
https://www.videogamesblogger.com/2016/02/08/xcom-2-achievements-guide.htm

Here's an Experimental Items List:
http://xcom.wikia.com/wiki/Proving_Ground

And a Weapons Guide by Ferry Groenendijk:
https://www.videogamesblogger.com/2016/02/08/xcom-2-weapons-guide.htm

If you need help with the online trophy, here's a Boosting Forum on PlaystationTrophies:
https://www.playstationtrophies.org/forum/xcom-2-a/296416-trophy-boosting-thread-read-first-post.html

Lastly, here's a basic Trophy List:
https://www.exophase.com/game/xcom-2-ps4/trophies/