Impossible lost Achievement regret?

[StarHeart333 1,765]

Whether it's due to online features gone  a game dlc no longer available, or broken game/glitches have you ever had an achievement you really wanted but failed to get before it was permanently locked out of possibility?

For myself it was telltales game of thrones I didn't have the money for the extra chapter and by the time I did it was gone so I only have chapter 1 achievements on my 360.

And now the game is literally impossible to get.

[Deae Rising Shine~ 55,832]

Certainly was onine trophies that weren't too bad to get, but I was busy with other games. And now servers are closed. Like WipEout HD for example. And some DLC that aren't sold anymore.

[StarHeart333 1,765]

Not so much impossible but just difficult is my trying to get the Richter achievement in Castlevania sotn. He is such a glass canon it's HARD trying to get through the inverted castle part. Every little hit does so much damage it's absurd. 

 

[Nitobit 1,861]

How did I miss this topic? 

In Mad Max there's an achievement for completing all non-repeating challenges, and one of them requires obtaining enough scrap through a stronghold upgrade that needs internet connection to work. It's unobtainable now, since servers went down. I didn't know about it until I was almost finished with the achievements.

Fortunately, I found a fully completed save file somewhere on the internet, so I was able to 100% it. I only used it when everything else was done, so it wasn't cheating.