Blacksad: Under the Skin

The alternate scenes the trophy is referring to is the cemetery scene at the start of the ending sequences. The primary factor for these scenes is if Mary is alive or not followed by Sonia’s status. What makes this trophy one of the most time consuming trophies is the fact that the choices that determine Mary’s status are made within the first quarter of the game with Mary’s death happening half way. You also cannot simply complete the game, reload the chapters where you made the choices that determined Mary’s status, change those then reload to the last chapter of the game. Those changes will not carry through to subsequent chapters automatically and the game also must be played from when those changes are made onwards to have an effect on the ending. Pair this up with the fact that you cannot skip dialogue, cut scenes, or investigation points, and you’re pretty much replaying most of the game in its entirety.

Then there is determining Sonia’s status. While those determining factors happen at the very end of the story, there are two things to make this more tedious than it has to be. The chapter select in the progress menu does not work as it should, as the last page does not put you where Thorpe and Sonia return to his office like the page states, which is half-way through that chapter. Rather, selecting the last page puts you at the beginning of that chapter, meaning you'll need to redo the same investigations that you are unable to skip through. The second thing is that you must sit through the whole ending and the credits which do not have an option to skip through. The game autosaves at the start of the ending sequence as it is the start of a Chapter, however it does not count as watching the ending until you are past the credits and reload a level and then trip an autosave. Ideally, you’ll be watching all three endings, one after the other. With the first set, watch all three variants, load a level, and trip an autosave to make sure the last ending you just watched is saved.

To shorten your second playthrough, make the following considerations during your first playthrough (spoiler warning!): 

Interact with every hotspot, every single clue, and every dialogue option (while making the appropriate choices that will not lock you out of requirements for other trophies that you plan on getting during your second playthrough) and make every deduction possible with the clues available when you are exploring the gym and diner when you first arrive and after going back to Blacksad’s office for his lock picks before progressing the plot further by calling Smirnov to meet Blacksad at the diner. The special choices to make note for planning is Mary’s job conversation and telling Sonia about her late father’s relationship. With Mary, make sure to tell her to continue working at the gym. With Sonia, exhaust all her dialogue options EXCEPT for the topic of who had her mother’s wedding ring; do not explore this dialogue path at all. Once you have interacted with everything you possible have done everything except for the topic of the ring, call Smirnov. Complete that sequence and continue playing, again without talking to Sonia about the ring. This will lead to Mary's death.

Once you have watched all three endings variances that required Mary to be deceased, press options when on the main menu to access the progress option. Select page 11, the diner scene with Smirnov, and replay the game from here. You will not have to redo any of the conversations or deductions that you did before meeting Smirnov at the diner. The only thing you will have to do to progress the plot now is just make the deductions about Joe Dunn’s death. However, before making those deductions, head back to the gym and tell Sonia the truth about who had her mother’s ring. This will now result in Mary surviving the events of the story. Continue your second playthrough from here, you will be able to make changes in choices that determine Sonia’s status at the end of the game where you can to watch the rest of the endings.

There are some glitches I encountered when testing this time saving method in version 1.02. The first is going back to talk to Sonia after the meeting will Smirnov, you will find a hotspot for Mary's purse on the floor in front of the office which will not be there and you'll find that you cannot go down stairs. You can either shut down the application and continue or once you talk to Sonia, make the deduction about Dunn's death that moves Blacksad to the scene of the crime. The second is once you arrive to the point in the story where the break in at the gym happens, it might have Mary scripted as the one to die. Simple shut down the application and continue and that should fix the issue and the purse found should now be different.

Endings where Mary is deceased:

1. Sonia is deceased: Yale kneels at the Dunn family grave with Blacksad comforting him with Mary’s grave insight.
2. Sonia incarcerated: Yale kneels at the Dunn family grave (minus Sonia) with Blacksad comforting him with Mary’s grave insight.
3. Sonia is alive and free: Sonia kneels at the Dunn family grave with Blacksad comforting her and with Yale at Mary’s grave.

Endings where Mary is alive:

1. Sonia is deceased: Mary kneels at the Dunn family grave with Yale comforting her and Blacksad watching from a distance.
2. Sonia incarcerated: Mary kneels at the Dunn family grave (minus Sonia) with Yale comforting her and Blacksad watching from a distance.
3. Sonia is alive and free: Mary kneels at the Dunn family grave with Sonia comforting her and Blacksad watching from a distance.

The advice you offer to both the boxers at the very latter part of the story does not factor into the story's ending(s).