Friendship

Friendship (commonly referred to as Happiness, which Polished Crystal's code uses) works in the same way as vanilla, ranging from 0 to 255. The game has buffed some of the existing methods and introduced new ones.

All Pokémon have a Base Friendship of 70 points as in Gen. II. Those caught in a Friend Ball come with 200 points, and the Friendship evolution requires 220+ points as in Gen. II–VII. (pokemon_data_constants.asm)

Thanks to TMs being infinite with their friendship increase still available (as in Gen. V), most Pokémon can easily reach 200 points.

List of Friendship Increase and Decrease

Some events vary in the amount according to the current points. Some have greater gains than in vanilla. (happiness_changes.asm, happiness_probabilities.asm)

Category	Event	0–99	100–199	200–	(ID)
Battle	Level-up	+5	+4	+3	#1
Battle	Level-up at met location	+10	+8	+6	#20
Battle	Battle against Gym Leader etc.	+5	+4	+3	#5
Battle	Faint	-1	-1	-1	#7
Battle	Faint against a opponent 30 levels stronger or more	-5	-5	-10	#9
Field	Poison survival with 1 HP	-5	-5	-10	#8
Field	256 steps	+2	+2	+1	#23
Item	Vitamin	+5	+3	+2	#2
Item	X Item	+1	+1	+0	#3
Item	EV-lowering Berry	+10	+5	+2	#4
Item	TM & HM	+1	+1	+0	#6
Item	Herbal: Heal/Energy Powder	-5	-5	-10	#16
Item	Herbal: Energy Root	-10	-10	-15	#17
Item	Herbal: Revival Herb	-15	-15	-20	#18
NPC	Haircut: the younger, 60%	+5	+5	+5	#10
NPC	Haircut: the younger, 10%	+10	+10	+10	#11
NPC	Haircut: the younger, 30%	+20	+20	+20	#12
NPC	Haircut: the elder, 30%	+10	+10	+10	#13
NPC	Haircut: the elder, 20%	+20	+20	+20	#14
NPC	Haircut: the elder, 50%	+40	+40	+40	#15
NPC	Daisy's Grooming	+3	+3	+1	#19
NPC	Photograph	+5	+3	+2	#21
NPC	Shrine Blessing	+5	+3	+2	#22