(Inspired by Songbird RPG)

When you give someone your liver (anchored in diegetics/roleplaying) they get the benefit of the equivalent of a level 3 Aid spell on them (10 hp for 8h). Also write them as a bond on your sheet.

Two characters that have traded livers can help each other with a d4 once per long rest. If they have traded multiple livers it increases to d6, d8 etc.

• An NPC that have given their liver to someone (PC or NPC) can call in any one favor anytime they like.
• A PC that gives their liver to someone (PC or NPC) can get advantage on a roll against them one time that day
• Two ways to get out of this
  • Give them your liver back (creating a relationship instead), or
  • Tell them a secret

You start with 1 liver but there is no cap.