vengeful
vindictive /vɪnˈdɪktɪv/ /vɪnˈdɪktɪv/
spiteful /ˈspaɪtfl/ /ˈspaɪtfl/
unforgiving /ˌʌnfəˈɡɪvɪŋ/ /ˌʌnfərˈɡɪvɪŋ/