; [wDamage] += a
AddToDamage:
push hl
ld hl, wDamage
add [hl]
ld [hli], a
ld a, 0
adc [hl]
ld [hl], a
pop hl
ret
; [wDamage] -= a
SubtractFromDamage:
push de
push hl
ld e, a
ld hl, wDamage
ld a, [hl]
sub e
ld [hli], a
ld a, [hl]
sbc 0
ld [hl], a
pop hl
pop de
ret