Martyr's Sacrifice (3.5e Maneuver)

''The cleric is barely standing when an arrow flies out of the air and strikes her. But no wound shows upon her body as a gash opens up on your own.''

As an immediate action you take an attack or dangerous effect meant for another ally in 60 feet for yourself. They take no penalties as if they had never been struck or targeted, while you become the new target. The attack goes against your AC and you take the damage or make the saving throw as normal. You may use this to keep an ally alive from an otherwise fatal blow. If the attack would kill you, you are able to be revived free of gold or XP cost.

This maneuver is a supernatural ability.