Do you have a link to something showing it actually removes tp/hp/mp from the mob? I had thought it was like samba and just created extra hp/mp/tp for you.
Edit: If it hasn't been done, the best way, I'd think - something that can charm + use twi knife, hit a mob 1x, get a tp drain on that hit, charm, check tp. If you keep solid track of how much tp it should have, can just charm after the first tp drain and check then, but proc on first hit seems best.
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