There are a handful of optional side quests to embark on in Stray. These tend to be some sort of collectable hunt, and they are, for the most part, fairly straightforward. Even in the largest areas, it’s not too difficult to bump into one or two collectables when blazing down the beaten path.
Related: Stray: Beginner's Guide
The first kind of collectable you are likely to bump into is the humble Music Sheet. This acts like a soft introduction to the game's exploration mechanics and will have you exploring high and low if you want to find them all. Of course, there is a reward for your hard work, and in fact, there are even some extra quests you can find whilst you potter around on this one.
If you want to start the Music Sheet quest, all you have to do is find the sad robot who has a guitar - but no music to play. You can find him almost immediately when starting entering the slums - after you’ve met the Guardian.
From the plaza, simply head left (opposite direction to the Barterman). You will see Morosque sitting next to some pillows holding his guitar. Talk to him, and you are good to go.
Technically you can get all the Music Sheets BEFORE talking to him if you wanted to.
Music Sheet one can be found just by going through the main story whilst in the slums. Your first objective will be to go to Momo’s apartment. You can find the Music Sheet here, in a storage room. You can squeeze through the metal bars in the door to gain access.
You will want to come back to this one since it is very easy to grab once you have grabbed a few others - specifically Music Sheet 6. When leaving Clementine’s place, hop onto the pipe to the left of the window, and climb onto the balcony. On the table, you will find the Music Sheet.
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