Life force is determined by heritage, such as Senju and Uzumaki having above average life force, while Uchiha only have normal life force. The absorption of life force, as such, will be denied unless states otherwise, as going from passive 0 stat bonus to passive 50 stat bonus mid combat and stacking that by touching more Uchiha and that stat bonus being PERMANENT is a bit too far. Please remove.
Also, just for me to clarify two things, one, can this be used during combat? I suspect it can, but just wanted to know. Two, by this description are you saying that every single Uchiha automatically has this seal on them?
And one more thing, being as it is that it is a seal "placed on birth" you cannot have it work on those with Sharingan implants, unless somehow they were adopted by you in their childhood which in most cases is unlikely, unless they've got some real orphan daddy issues. If you wish, you may create another jutsu that creates the seal and you can place it on those who do not already have it, but, due to the effects of this jutsu I presume that to be a much more difficult process to complete if it were to be registered.
Speaking of effects, they are very much so likened to a poison so, if there is a duration, please state how long it takes for an activated individual to die. I.e. at first post they vomit, seconed post bleeding, etc. etc. all that good stuff.
Thank you!
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