how to change the skill "possess"

yea i looked at metroid quest's game with windhex and all the possess values are the same

C2/17E5: BB TYX
C2/17E6: 20 C1 19 JSR $19C1 (targetting ?)
C2/17E9: A9 20 LDA #$20
C2/17EB: 0C A4 11 TSB $11A4 (Set can't be dodged)
C2/17EE: A9 A0 LDA #$A0
C2/17F0: 8D A9 11 STA $11A9 (Stores Possess in special effect)
C2/17F3: 4C 7B 31 JMP $317B (Character execute one hit)

nothing is changed there... hmm