The diamond achievement means it’s a rare achievement (something like less than 5 or 10% of people have earned it). The platinum trophy signifies you have earned every other available trophy for the game (excluding DLC trophies). Xbox used to have something similar on the 360 where you could see the games that you earned every achievement on.
Microsoft Is Interested In Bringing Trophy-Like Platinum Xbox Achievements (twistedvoxel.com) angielski
Starfield has been cracked (i.redd.it) angielski
Sony raising PS Plus pricing by 33% (www.pushsquare.com) angielski
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