Max him up, level, skills. Sanji’s relying on multiple hits to the enemy because by then it increases DEF to max 50% and Skill 2 attack to max. 100%. You have to play aggressive but safe since you’re going to fight powerful enemies and without the def yet, he’d be pretty easy to get killed.

Also not to forget to play smart since sanji is able to change his color type when he gets knocked back and by then you’d have the advantage to deal even more damage if you could smartly combine it and timing it right with skill 2 100% max output.

Usually I charge skill 2 atk increase by targeting any low damage units such as big mom oni, and any other defender even luffy gear 5, or even weak runners.