- Priorities for spending your blood crystals: Buy drinks till you get the computer upgrade, then buy the movement upgrades, then buy info from Crimson, then unlock fast travel points. Though do unlock some fast travel points close to suspects to save yourself some time. Blood crystals are everywhere so you shouldn't be hungry for them after a little bit, especially once you get the double jump and the air dash and you can basically fly around the island.
- Every trash can and cupboard, or at least the vast majority, have a blood crystal in them. If it has a pink lid and you can open it it's probably got a blood crystal in it.