Death

If a character is dead, and a resurrection is attempted by a spell or spell effect with longer than a 1 action casting time, a Resurrection Challenge is initiated. Up to 3 members of the adventuring party can offer to contribute to the ritual via a Contribution Skill Check. The DM asks them each to make a skill check based on their form of contribution, with the DC of the check adjusting to how helpful/impactful the DM feels the contribution would be.
For example, praying to the god of the devout, fallen character may require an Intelligence (Religion) check at an easy to medium difficulty, where loudly demanding the soul of the fallen to return from the aether may require a Charisma (Intimidation) check at a very hard or nearly impossible difficulty. Advantage and disadvantage can apply here based on how perfect, or off base, the contribution offered is.
After all contributions are completed, the DM then rolls a single, final Resurrection success check with no modifier. The base DC for the final resurrection check is 10, increasing by 1 for each previous successful resurrection the character has undergone (signifying the slow erosion of the soul’s connection to this world). For each successful contribution skill check, this DC is decreased by 3, whereas each failed contribution skill check increases the DC by 1.
Upon a successful resurrection check, the player’s soul (should it be willing) will be returned to the body, and the ritual succeeded. On a failed check, the soul can make one final plea with the God(dess) of Death to come back to life. If this is done the player character will be on borrowed time. The days of the borrowed time depend on the maximum HP of the player character. Each day the player character will lose 1 HP from their maximum until they reach 0. Only the player character who has made a succesful deal may know about this deal, if they tell anyone else the deal will be forfeited and the player character will die immediately.
For example: Ronan makes a succesful case to the Goddess Freyja to give him some extra time. When Ronan is resurrected he still has his maximum amount of 71 HP. This means that he can live for another 71 days. After being alive for 30 days he can feel himself become weaker, he can take less hits and the gloom of death is hanging over him. Ronan breaks and tells his companions about the deal he made. As soon as the words have left his mouth time seems to stop for Ronan as an angered Freyja stands in front of him. She curses him for his disobediance and disrespect towards her generous offer and takes Ronan's soul out of his body. For Ronan's companions it is a matter of seconds where Ronan has uttered the words and falls lifeless onto the ground.
Only the strongest of magical incantations can bypass this resurrection challenge, in the form of the True Resurrection or Wish spells. These spells can also restore a character to life who was lost due to a failed resurrection ritual.
If a spell with a casting time of 1 action is used to attempt to restore life (via the Revivify spell or similar effects), no contribution skill checks are allowed. The character casting the spell makes a Rapid Resurrection check, rolling a d20 and adding their spellcasting ability modifier. The DC is 10, increasing by 1 for each previous successful resurrection the character has undergone. On a failure, the character’s soul is not lost, but the resurrection fails and increases any future Resurrection checks’ DC by 1. No further attempts can be made to restore this character to life until a resurrection spell with a casting time higher than 1 action is attempted.