There are five Memories of your Father in the Iki Island Expansion for Ghost of Tsushima: Director’s Cut. These are completely optional but if you’re aiming for all Trophies, must be completed towards that goal. These are a new type of collectable where Jin will relive his past and you’ll obtain a small Legend increase and a Sword Kit.
Memory of Sorrow - Thunderhead Cliffs
You’ll find this memory to the far northeast of Iki Island, at the Thunderhead Cliffs. This memory requires you to to down the cliff to speak with a soldier to obtain some Sake, before returning to Kazumasa.
Memory of Foreboding - East of Tatsu’s Ladder
The next memory is located down on the shore, far to the east of Tatsu’s Ladder. Once you begin the memory, you’ll need to follow the man that informs you of Kazumasa’s coming speech, don your armor and then join him at the top of the camp.
Memory of Anguish - Kemono Trail
This memory is located along the southwest edge of Kemono Trail, follow the path and you’ll locate the start point overlooking the Kidafure Battleground. During the memory, your only task is to simply follow the man and watch the scenes play out.
Memory of Kinship - Senjo Gorge
The next memory can be found by heading to Senjo Gorge, north from the Haiku located in the same area. Once again, simply follow the man in this memory to complete it.
Memory of an Unfinished Song - Sly Hunter’s Forest
This final memory is not available until you’ve seen all the others, at which point Jin remarks about something still troubling. This will add a final memory to your map, in Sly Hunter’s Forest. During the memory, head to the large tent and interact with everything there, for completing this final memory, you’ll obtain the Tempest’s End Sword Kit and unlock Elegy for Kazumasa.