As already suggested in previous answers, 'narcissistic personality disorder', 'scheming' and 'manipulator' are most suitable for your case, but if the person uses unusually (deceptively) passive or indirect tactics, you might consider passive-aggressive personality:
passive–aggressive : being, marked by, or displaying behavior characterized by the expression of negative feelings, resentment, and aggression in an unassertive passive way
It is passive-aggressive behavior, the donning of a mask of amiability that conceals raw antagonism toward one's competitors, even one's friends. — Hilary De Vries
Passive-aggressive behavior is fundamentally deceptive aggression, where the inner resentment is cloaked by an outer pretence of placidity or neutrality and antagonism is expressed not through open hostility but through manipulative behavior (whuch can even include subtle lying, turning people against somebody, and feigning hurt or illness to elicit sympathy). It is not so easy for others to recognize or identify passive-aggressive behavior. Here "donning a mask of amiability that conceals raw antagonism" is possibly the part that fits your case.