I wouldn't mind a late game utility item that has your champion make a contract with the dead..
It only truly activates when you die. Like some sorta evil twin to
. A contract with the underworld is written in stone and when you die a portion of your power will empower a teammate of choice for the duration of your death timer in exchange for a longer death timer if you do die after channeling the item. When you channel the item you become cursed, temporarily your max HP / Mana is a bit less than usual which is part of completing the ritual to active the items true purpose. Its unique in the way of gambling because it would be gambling.
Basically if your gamble fails you pay the price and could cost the reliability of your presence around your team. If your gamble wins you can possibly manage to secure a major shutdown , objective or even winning the game itself..
Its your choice at the end.
Possible build path :
** [The Pact] **
+
+ 
Support becomes meta.
Not only has she died for us. She lives through us now.