上位 - superiority in terms of status 威压 - suppression It should be -something- Suppression. You might've heard of 'bloodline suppression', 'coercion', 'absolute suppression' and the like before. Since this is a blood clan, I would choose to use bloodline suppression here even though the meaning of 上位 is slightly different (since it's more closely tied to status). However, it wouldn't be out of line in terms of the blood clan.
Thanks for the suggestions. bloodline suppression would do if he used it on another kindred, but he used it on a demonic beast...