Someone earlier mentioned the DLC for Dark Souls, well all Fromsoft games are like that, theres no need, for example:
- 2 - Find 3 keys and go to specific statues that you will have seen in the base game, the SotFS edition even changes where these keys are - Tbh this one is not too bad as it is foreshadowed
- 3 - Go back to an NPC that was in the first 3rd and he teleports you there and you can access both DLC from there so thats ok, a bit obtuse but the Trailers gave it away
- Bloodborne - The Worst one, you need to be either in a New Game or start from New Game+ if you've got past a certain part of the game, find a certain enemy, btw its invisible if you haven't gained enough insight and stand there whilst it looks like its gonna kill you, allow it to capture you and teleport you to the DLC area, the only thing I can think of in terms of a clue is early in the game if you die to a certain enemy you get moved to a New area which is a prison. That's it
If you want a more older example,
Goldeneye has one level early on that doesn't tell you what to do and can be softlocked if a NPC dies or decides to not do the actions needed to progress the level, but the game literally does not give a fail state until you walk to the end of the level either