this item would work opposite to assasin medal.
it will ignore the hero on the list while highest sequence is the last to focus.

it would have the game much more strategic and look like real dota ,When a super tanky hero come to the front your team keep attack him and their back line with low survivability just free hitting you. that make the game frustrated and ppl blame that was stupid AI.

It may be game broken or unbalance? i dont thing so. It will create many many new strategy to win the game. and tanky superman strategy that ruin every mid game in current meta will be less common strategy.