The Gift Exchange is a core gameplay mechanic that appears in Onimusha 2: Samurai's Destiny that becomes available once Jubei Yagyu meets Ekei Ankokuji and Magoichi Saiga in Imasho, and is directly connected to the scenario system that is also present within the game.
Alongside the player's standard item inventory, there exists a separate inventory exclusive for gift items that can be given to Ekei Ankokuji, Magoichi Saiga, Kotaro Fuma and Oyu. A total of 125 gifts can be found throughout the game, and each will elicit a different response depending on who it is given too, as well as some eliciting responses depending on when or where the gift is given. When a gift has been given to an ally, their friendship will increase or decrease depending on how much they like the gift, making this the only way to increase a character's friendship level and triggering scenarios involving them should their friendship be raised high enough after being given enough gifts. Some gifts can be given alongside other gifts in order to significantly raise their effect on a character's friendship above what they would normally grant.
While there is no way to view the exact level of friendship a character is, their initial animation when being given a gift will give the player a general idea as to whether they are negative, neutral or positive towards Jubei. When at a low friendship level, all characters will be facing away from the player before turning around to face them. When at medium level of friendship, they will face Jubei immediately rather than turning towards him. When at a high level of friendship, each character will perform a unique animation to signify as such when given something. Ekei will wave at Jubei, Magoichi will salute with his weapon, Kotaro will drop from the ceiling, and Oyu will have her hands behind her back.
Every character starts the game at 300 friendship, though Kotaro's is not set until he becomes available for the player to interact with through one of his three meeting scenarios, instead being set to 0 until he has been met. Whenever a gift is given to an ally, the friendship for all other allies drops by 2 (except for Kotaro if he hasn't been met yet). This includes Oyu even before her meeting after obtaining the Faith Orb as her friendship is set to 300 as soon as the game begins. An ally's reaction to a gift can vary between seven different responses, each with different effects on that character's friendship.
There are also ways for friendship to be affected during combat sections. When entering an area and finding a character already fighting, or if a character appears to aid you against enemies, their friendship will immediately drop by 100. If the player defeats all enemies and completes the combat encounter, the aforementioned drop in friendship will be regained. The combat encounter will be completed when the character leaves the area themselves or becomes interactable, remaining in a "Draw" position (R1 pose) if there are any enemies remaining or have yet to appear. If the player leaves the area before all enemies are defeated and the combat encounter has been completed, they will not regain the 100 friendship. Friendship will also drop by 5 when an ally is not saved after being restrained by a Baby, while their friendship will increase by 10 if the player rescues them by damaging the Baby.
Rank
Friendship
Character Reaction
A
+50
Very Happily Accepts Gift
B
+30
Fairly Happily Accepts Gift
C
+10
Accepts Gift
D
-10
Reluctantly Accepts Gift
E
-30
Lightly Rejects Gift
F
-50
Firmly Rejects Gift
G
-70
Given something they had previously given the player
When a gift is accepted, Jubei will receive a gift in return based on the character's reaction to Jubei's gift, with each character having a separate pool of items for each rank. The gift usually received is chosen at random, though a select few gifts are guaranteed to be given in exchange for certain gifts, and each rank has one gift that can be given repeatedly.
